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851.
Ruping Mo Paul I. Joe Chris Doyle Paul H. Whitfield 《Pure and Applied Geophysics》2014,171(1-2):323-336
A brief review of the anomalous weather conditions during the Vancouver 2010 Winter Olympic and Paralympic Games and the efforts to predict these anomalies based on some preceding El Niño–Southern Oscillation (ENSO) signals are presented. It is shown that the Olympic Games were held under extraordinarily warm conditions in February 2010, with monthly mean temperature anomalies of +2.2 °C in Vancouver and +2.8 °C in Whistler, ranking respectively as the highest and the second highest in the past 30 years (1981–2010). The warm conditions continued, but became less anomalous, in March 2010 for the Paralympic Games. While the precipitation amounts in the area remained near normal through this winter, the lack of snow due to warm conditions created numerous media headlines and practical problems for the alpine competitions. A statistical model was developed on the premise that February and March temperatures in the Vancouver area could be predicted using an ENSO signal with considerable lead time. This model successfully predicted the warmer-than-normal, lower-snowfall conditions for the Vancouver 2010 Winter Olympics and Paralympics. 相似文献
852.
Wing Yin Mo Zhang Cheng Wai Ming Choi Yu Bon Man Yihui Liu Ming Hung Wong 《Marine pollution bulletin》2014
Food waste was collected from local hotels and fish feed pellets were produced for a 6 months long field feeding trial. Three types of fish feed pellets (control diet: Jinfeng® 613 formulated feed, contains mainly fish meal, plant product and fish oil; Diet A: food waste based diet without meat and 53% cereal; Diet B: food waste based diet with 25% meat and 28% cereal) were used in polyculture fish ponds to investigate the growth of fish (grass carp, bighead and mud carp), changes in water quality and plankton density. No significant differences in the levels of nitrogen and phosphorous compounds of water body were observed between 3 fish ponds after the half-year feeding trial, while pond receiving Diet A had the highest density of plankton. The food waste combination of Diet B seems to be a better formulation in terms of the overall performance on fish growth. 相似文献
853.
Lactococcosis is prevalent on grey mullet (Mugil cephalus) in Hong Kong aquaculture resulting in serious economic loss. A compound formulation of Traditional Chinese Medicines (TCM) (modified Huanglian Jiedu decoction (HLJDD)) comprising Rhizoma coptidis, Radix scutellaria, Cortex phellodendri, Fructus gardeniae, Fructus forsythiae and Flos lonicerae japonicae (in a ratio of 3:2:2:3:3:5) were applied as feed supplements to deal with the disease. The Nitroblue tetrazolium activity in blood, bactericidal activity and total immunoglobulin in plasma were significantly enhanced after feeding 1% of this TCM for 28 days. The disease resistances to Lactococcus garvieae in 1% and 2% TCM feeding groups were significantly enhanced. In the in vitro study, the modified HLJDD also activated the plasma bactericidal activities (p < 0.01). Based on this study, 1% modified HLJDD feeding for 28 days may be an optimal dose to prevent L. garvieae infection and could be used in aquaculture industries. 相似文献
854.
2008年5月12日14时28分,汶川8.0级大地震发生时,我国前兆台网在网运行的七十多套钻孔体应变仪中,除个别仪器雷击或探头损坏外,其余运转基本正常,几乎全部记录到了此次地震。其中位于震中方圆1000km范围内的共有12套仪器,均为“十五”新上的TJ系列应变仪,包括了四川、甘肃、陕西3个受灾最严重省份的全部体应变仪,以及宁夏、云南、山西的部分仪器,分析结果如下。 相似文献
855.
We demonstrate that GA-MHYPO determines accurate hypocentral parameters for local earthquakes under ill conditions, such as limited number of stations (phase data), large azimuthal gap, and noisy data. The genetic algorithm (GA) in GA-MHYPO searches for the optimal 1-D velocity structure which provides the minimum traveltime differences between observed (true) and calculated P and S arrivals within prescribed ranges. GA-MHYPO is able to determine hypocentral parameters more accurately in many circumstances than conventional methods which rely on an a priori (and possibly incorrect) 1-D velocity model. In our synthetic tests, the accuracy of hypocentral parameters obtained by GA-MHYPO given ill conditions is improved by more than a factor of 20 for error-free data, and by a factor of five for data with errors, compared to that obtained by conventional methods such as HYPOINVERSE. In the case of error-free data, GA-MHYPO yields less than 0.1 km errors in focal depths and hypocenters without strong dependence on azimuthal coverage up to 45°. Errors are less than 1 km for data with errors of a 0.1-s standard deviation. To test the performance using real data, a well-recorded earthquake in the New Madrid seismic zone and earthquakes recorded under ill conditions in the High Himalaya are relocated by GA-MHYPO. The hypocentral parameters determined by GA-MHYPO under both good and ill conditions show similar computational results, which suggest that GA-MHYPO is robust and yields more reliable hypocentral parameters than standard methods under ill conditions for natural earthquakes. 相似文献
856.
基于TOUGHREACT并行版,建立了苏北盆地盐城组下段砂岩层在碳封存中的CO2-水-岩反应二维径向模型,并评估储层的矿物封存潜力,探讨分析了网格剖分精度和储层各向异性对矿物封存模拟的影响。模拟结果表明:在CO2封存过程中,片钠铝石、方解石和菱铁矿沉淀较明显,在CO2注入5 000a后矿物封存的比例高达34.0%;网格剖分精度的不同对矿物封存反应路径没有影响,但粗网格模型计算得到的矿物封存量偏高;降低储层的kv(垂向渗透率)在短期内会促进CO2的水平运移,有利于溶解和矿物封存;但随着时间延长,降低kv对对流作用的抑制开始体现,表现为1 000a后中等kv值的模型计算出的矿物封存量高于较大kv和较小kv值的模型。 相似文献
857.
858.
目前储集层分类方法多数只是从储集层的物性特征角度进行分类,而没有从储集层的成因机制进行分类。通过利用分析化验资料、钻测井资料和测试资料,对北部湾盆地乌石凹陷东区始新统流沙港组三段Ⅱ油组(L3Ⅱ油组)的沉积特征、成岩作用和构造特征进行分析,进而研究其对储集层物性的影响,并对储集层进行分类。结果表明: L3Ⅱ油组主要发育扇三角洲内前缘水下分流河道、外前缘水下分流河道和席状砂3种沉积微相;成岩相主要识别出泥质杂基充填相、不稳定组分溶蚀相和强压实致密相3种成岩相;裂缝相则以无裂缝相为主,局部可观察到高角度和网状裂缝相。在此基础上通过三者的叠加对储集层的岩石物理相进行分类命名,划分出内前缘水下分流河道—泥质杂基充填相—高角度裂缝相等9种不同的岩石物理相。根据不同的岩石物理相特征,总结归纳出了Ⅰ类好储集层、Ⅱ类中等储集层和Ⅲ类差储集层共3类储集层,实现了从储集层成因机制的角度对储集层进行分类和评价。 相似文献
859.
Heeok Jung Yong-seok Jang Jung Mo Lee Wooil M. Moon Chang-Eob Baag Ki Young Kim Bong Gon Jo 《Tectonophysics》2007,429(3-4):253-265
We analyzed the short period Rayleigh waves from the first crustal-scale seismic refraction experiment in the Korean peninsula, KCRUST2002, to determine the shear wave velocity and attenuation structure of the uppermost 1 km of the crust in different tectonic zones of the Korean peninsula and to examine if this can be related to the surface geology of the study area. The experiment was conducted with two large explosive sources along a 300-km long profile in 2002. The seismic traces, recorded on 170 vertical-component, 2-Hz portable seismometers, show distinct Rayleigh waves in the period range between 0.2 s and 1.2 s, which are easily recognizable up to 30–60 km from the sources. The seismic profiles, which traverse three tectonic regions (Gyeonggi massif, Okcheon fold belt and Yeongnam massif), were divided into five subsections based on tectonic boundaries as well as lithology. Group and phase velocities for the five subsections obtained by a continuous wavelet transform method and a slant stack method, respectively, were inverted for the shear wave models. We obtained shear wave velocity models up to a depth of 1.0 km. Overall, the shear wave velocity of the Okcheon fold belt is lower than that of the Gyeonggi and Yeongnam massifs by 0.4 km/s in the shallowmost 0.2 km and by 0.2 km/s at depths below 0.2 km. Attenuation coefficients, determined from the decay of the fundamental mode Rayleigh waves, were used to obtain the shear wave attenuation structures for three subsections (one for each of the three different tectonic regions). We obtained an average value of Qβ− 1 in the upper 0.5 km for each subsection. Qβ− 1 for the Okcheon fold belt ( 0.026) is approximately three times larger than Qβ− 1 for the massif areas ( 0.008). The low shear wave velocity in the Okcheon fold belt is consistent with the high attenuation in this region. 相似文献
860.
ZHANG Gongcheng FENG Congjun YAO Xingzong JI Mo YANG Haizhang QU Hongjun ZENG Qingbo ZHAO Zhao SUN Rui 《《地质学报》英文版》2021,95(1):1-20
Deepwater oil and gas exploration has become a global hotspot in recent years and the study of the deep waters of marginal seas is an important frontier research area.The South China Sea(SCS)is a typical marginal sea that includes Paleo SCS and New SCS tectonic cycles.The latter includes continental marginal rifting,intercontinental oceanic expansion and oceanic shrinking,which controlled the evolution of basins,and the generation,migration and accumulation of hydrocarbons in the deepwater basins on the continental margin of the northern SCS.In the Paleogene,the basins rifted along the margin of the continent and were filled mainly with sediments in marine-continental transitional environments.In the Neogene–Quaternary,due to thermal subsidence,neritic-abyssal facies sediments from the passive continental margin of the SCS mainly filled the basins.The source rocks include mainly Oligocene coal-bearing deltaic and marine mudstones,which were heated by multiple events with high geothermal temperature and terrestrial heat flow,resulting in the generation of gas and oil.The faults,diapirs and sandstones controlled the migration of hydrocarbons that accumulated principally in a large canyon channel,a continental deepwater fan,and a shelf-margin delta. 相似文献