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51.
以吉林省境内红星构造带(已发现油田)和杨柳青构造带(未发现油田)为试验区,首先利用地震地层学方法,研究间接参数特征,确定有利相带和有效圈闭,并在有效圈闭上选择了39个2×2cm时窗。在时窗内提取与地震波动力学有关的信息,即频率、振幅、频谱能量等,然后对这种信息进行统计计算,获得振幅方差等九个参数并对其进行综合分析,从已知油气藏出发,对未知圈闭油气状况进行了三级预测,指出了最有利的勘探靶区。 相似文献
52.
Tidal effects on temperature front in the Yellow Sea 总被引:5,自引:0,他引:5
Temperature front (TF) is one of the important features in the Yellow Sea, which forms in spring, thrives in summer, and fades
in autumn as thermocline declines. TF intensity ⋎S
T
⋎ is defined to describe the distribution of TF. Based on the MASNUM wave-tide-circulation coupled model, temperature distribution
in the Yellow Sea was simulated with and without tidal effects. Along 36°N, distribution of TF from the simulated results
are compared with the observations, and a quantitative analysis is introduced to evaluate the tidal effects on the forming
and maintaining processes of the TF. Tidal mixing and the circulation structure adapting to it are the main causes of the
TF.
Supported by the National Basic Research Program of China (No. G1999043809) and the National Science Foundation of China (No.
49736190). 相似文献
53.
介绍了青海省兴海7.0级地震前水氡,地下水位,地表形变,地震活动性,气象及动物等出现的异常,并对震前的预报作了简介。 相似文献
54.
云南点苍山冰川湖泊沉积物磁化率的影响因素及其环境意义 总被引:12,自引:3,他引:12
文章通过对点苍山海拔3820m冰水沉积剖面的粒度参数、磁化率、氧化铁含量和有机质含量的综合实验分析,并讨论了这些指标的相互关系及其环境意义。实验结果表明,磁化率的强度与粗砂组分的含量成正相关,而与粘土等细粒组分含量成负相关;同时与有机质含量成负相关,与氧化铁含量成正相关。矿物组分分析实验表明,沉积物主要磁性来源于磁化铁。根据以上结果,结合冰川湖泊流域面积小、高寒环境的特点,其磁化率的影响因素与一般湖泊不同,认为冰川湖泊沉积中,因为物源较近导致外源磁性矿物主要赋存于粒度较粗的碎屑颗粒中,而高寒的环境条件使得有机质对沉积物的磁性矿物起到了稀释的作用,而很难有积极的贡献。根据磁化率的环境意义,恢复了全新世以来点苍山的古气候,从中可以划分6个不同的气候阶段:11.5~10.6kaB.P.,10.6~8.9kaB.P.,8.9~5.5kaB.P.,5.5~3.3kaB.P.,3.3~0.8kaB.P.和0.8kaB.P.至今,代表了末次冰期结束以后湖泊从产生至消亡的全过程。根据与其他相关地区的对比,分析了西南季风演变的一些规律。 相似文献
55.
TECTONIC FEATURES AND HYDROCARBON POTENTIAL OF THE EASTERN QAIDAM BASIN 相似文献
56.
Yang Guohua 《中国地震研究》2007,21(3):269-280
In order to track the space-time variation of regional strain field holistically(in a large scale) and to describe the regional movement field more objectively,the paper uses a nonlinear continuous strain model focused on extracting medium-low frequency strain information on the basis of a region with no rotation.According to the repeated measurements(1999~2001~2004) from GPS monitoring stations in the Sichuan and Yunnan area obtained by the Project of "China Crust Movement Measuring Network",and with the movement of 1999~2001(stage deformation background) as the basic reference,we separated the main influencing factors of the Kunlun Mountain M-S8.1 earthquake in 2001 from the data of 2001 and 2004,and the results indicate:(1) the Kunlun Mountain M-S8.1 earthquake has a discriminating effect on the Sichuan and Yunnan area,moreover,the deformation mode and background had not only certain similitude but also some diversity;(2) The movement field before the earthquake was very ordinal,while after the earthquake,order and disorder existed simultaneously in the displacement field;The displacement quantities of GPS monitoring stations were generally several millimeters;(3) The principal strain field before earthquake was basically tensile in an approximate EW direction and compressive in the SN direction,and tension was predominant.After the earthquake,the principal strain field in the Sichuan area was compressive in the EW direction and tensile in the SN direction,and the compression was predominant.In the Yunnan area,it was tensional in the NE direction and compressive in the NW direction,and tension was predominant;(4) The surficial strain before the earthquake was dominated by superficial expansion,the contractive area being located basically in the east boundary of Sichuan and Yunnan block and its neighborhood.After the earthquake,the Sichuan area was surface contractive(the further north,the greater it was),and south of it was an area of superficial expansion.Generally speaking,the Kunlun Mountain M-S8.1 earthquake played an active role in the accumulation of energy in the Sichuan and Yunnan area.Special attention shall be focused on the segment of Xichang-Dongchuan and its neighborhood. 相似文献
57.
???????????????????????μ?????????????????????????????Envisat??????????????????????????????????????,??????ο??????????????OCOG???Beta-5??3???????????????????????????????????Ч?? 相似文献
58.
59.
以从海南三亚近海海水中采集的样品为研究对象,利用平板筛选法筛到一株产酯酶的中度嗜盐菌菌株LYG1-1。通过形态学、生理生化及16S rRNA序列分析,发现该菌株为革兰氏阴性菌,其最适生长温度为30℃,最适生长pH为7.5,最适NaCl浓度为10%。16S rRNA基因序列分析显示,菌株LYG1-1与Halomonas salina亲缘性最近,16S rRNA基因序列相似性为99.72%。在含10%NaCl的0.05mol·L-1Tris-HCl(pH 8.0)缓冲液中,45℃条件下作用,酶活性最高,40℃处理24h仍保持83%的活性。金属离子浓度为5mmol·L-1时,Ca2+、Mg2+对菌株LYG1-1酶活具有明显的激活作用,Hg2+表现出强烈的抑制作用。 相似文献
60.
Cassiopeia A, the brightest radio supernova remnant(SNR) in the sky, has several unique characteristics in comparison to its peers. Besides its radio brightness and prominent soft-concave radio spectrum,its γ-ray spectrum appears to have a low-energy cutoff near 2 GeV, and it is the only SNR with prominent hard X-ray emission. While the unusual radio properties may be attributed to strong emission from reverse shocks, the hard X-ray emission has been associated with high-speed inward shocks induced by high density gases. Then, the low-energy γ-ray spectral cutoff could be attributed to slow penetration of lower energy particles accelerated near the inward shocks into high-density emission zone. In this paper,we carry out magneto-hydrodynamic(MHD) simulations of shocks in Cassiopeia A and demonstrate that its inward shock structure can indeed be reproduced via shock interactions with clumps of gases with a density of ~ 20 cm~(-3). 相似文献