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61.
济阳坳陷新生代主要生油岩系底界面温度分布 总被引:2,自引:2,他引:0
依据济阳坳陷千余口测温井的地温梯度数据和地层岩性描述、分层数据以及钻井资料,计算了该区各生油岩系底界面的温度。统计结果表明:济阳坳陷大部分地带沙河街组地层底界面温度介于90~150℃之间,目前仍具有大量生油的温度条件,而在一些凸起地区和斜坡地带,该地层组段温度普遍小于90℃,未能达到生油的温度指标;孔店组地层也具有一定的生油温度条件。研究表明,地层温度与地层界面埋深密切相关,温度随界面埋深的增大而升高,沉积厚度大的凹陷带界面温度大于沉积厚度小的凸起区或斜坡地带,说明地层界面埋深是决定地温高低的主要控制因素,而地温梯度对地层界面温度的影响相对较小。 相似文献
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杭州湾大型底栖动物季节分布及环境相关性分析 总被引:2,自引:1,他引:1
对杭州湾大型底栖动物进行了夏(2006年7-8月)、冬(2006年12月-2007年1月)、春(2007年4月)、秋(2007年10-11月)季调查,分析了大型底栖动物的季节分布及其与环境的关系。结果表明:本海域四季共鉴定出113种大型底栖动物,多毛类、软体动物和甲壳类是该海域大型底栖动物的主要类群;主要优势种为双鳃内卷齿蚕、西方似蛰虫和多鳃卷吻沙蚕等多毛类。方差分析表明,除甲壳类丰度外,杭州湾大型底栖动物群落参数无显著季节差异,群落分析表明,杭州湾群落特点比较单一,未分辨出显著差异的群落;丰度/生物量比较法分析表明,秋季杭州湾海域受到了污染的扰动;典范对应分析表明,多毛类主要受物理因子(如温度、盐度、水深等)影响,而软体动物、甲壳类和其他类动物主要受生物化学因子(如叶绿素、总有机碳、浮游生物等)影响。从典范对应分析的结果,可以推断出杭州湾大型底栖动物受自然环境特征的影响较人类活动的影响大。 相似文献
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使用高灵敏度的电容式微压波传感器对1998年4月11日16时发生在贵州省普定县的一次降冰雹过程的重力波进行观测,利用WRF(Weather Research and Forecast)中尺度模式对这一过程进行数值模拟,使用Morlet小波方法对模拟结果进行分析,得出这一过程中惯性重力波的分布和变化规律,并分析急流、地形及切变线对惯性重力波的影响.观测发现:在降冰雹前,每隔1~4小时出现一次短周期重力波阵性增强的现象.数值模拟结果显示:在低空降冰雹前几个小时有强的短周期重力波出现,其中周期较长的出现早、存在时间长,周期较短的出现晚、存在时间短;强的低空急流和风速垂直切变触发对流或湍流的发生和加强,对流或湍流又激发了80~200 min的短周期重力波;短周期重力波更容易向垂直方向传播,而长周期重力波倾向于水平方向传播.长周期重力波在降冰雹后周期有明显变短现象,随高度越加明显.由地形形成的重力波在最高山峰上空振幅最大. 相似文献
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对风暴相对螺旋度(SRH)的定义进行了介绍。通过对2007-2008年石家庄地区27次强对流天气过程进行了统计分析,找出短时暴雨、冰雹、大风任意组合时高、低层SRH的不同特征,得到不同天气现象的预报指标,并利用2009年的几次强对流天气过程进行了验证。结果表明:出现短时暴雨时,SRH低经常连续较长时间为正值,但数值较小,SRH高也是以正值为主;伴有冰雹或者大风时,SRH低、SRH高的差值迅速增大,SRH高可达到100m2•s-2或以上。 相似文献
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Ying Zhang Zhenbo Lv Bo Guan Yuanjin Liu Fan Li Shaowen Li Yuanqing Ma Junbao Yu Yunzhao Li 《洁净——土壤、空气、水》2013,41(10):1027-1034
Laizhou Bay, located in the northwest of Shandong Peninsula, has complex transitional environments between terrestrial and marine ecosystems. In the present study, a total of 122, 131, and 139 species were collected in spring, summer, and autumn 2011, respectively. Species constitutions of macrobenthos were grouped into four phyla, of which annelida were the most abundant phylum, the average biomass proportion of echinodermata was the lowest, and the proportion of important species for mollusca was the highest. The structure of the macrobenthic community showed significant differences between sites, and greater divergence was observed between the third site (S03) and other stations. The ABC plots showed that the biomass curve lay below the abundance curve, and the W‐statistic value was negative. The result of the BOPA index showed that two stations had moderate ecological status in spring and that there were two heavily polluted sites and one moderately polluted site in summer. The BIO‐ENV analyses indicated that the grain‐size fractions together with trace metals (Hg, Pb, Zn, Cu, and Cr) could be considered as the major environmental variables influencing the macrobenthic patterns. The results together demonstrated that the macrobenthic communities in Laizhou Bay were negatively affected, perhaps by the tremendous impact of heavy metals in the sediments. 相似文献
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Measurement and Analysis of Thermal Conductivity of Rocks in the Tarim Basin, Northwest China 总被引:3,自引:0,他引:3
: As a parameter that describes heat transmission properties of rocks, thermal conductivity is indispensable for studying the thermal regime of sedimentary basins, and retrieving high-quality data of thermal conductivity is the basis for geothermal related studies. The optical scanning method is used here to measure the thermal conductivity of 745 drill-core samples from the Tarim basin, the largest intermontane basin with abundant hydrocarbon potential in China, and water saturation correction is made for clastic rock samples that are of variable porosity. All the measured values, combined with previously published data in this area, are integrated to discuss the distribution characteristics and major controlling factors that affect the thermal conductivity of rocks in the basin. Our results show that the values of thermal conductivity of rocks generally range from 1.500 to 3.000 W/m·K with a mean of 2.304 W/m·K. Thermal conductivity differs considerably between lithological types: the value of a coal sample is found to be the lowest as being only 0.249 W/m·K, while the values for salt rock samples are the highest with a mean of 4.620 W/m·K. Additionally, it is also found that the thermal conductivity of the same or similar lithologic types shows considerable differences, suggesting that thermal conductivity cannot be used for distinguishing the rock types. The thermal conductivity values of mudstone and sandstone generally increase with increasing burial depth and geological age of the formation, reflecting the effect of porosity of rocks on thermal conductivity. In general, the mineral composition, fabric and porosity of rocks are the main factors that affect the thermal conductivity. The research also reveals that the obvious contrast in thermal conductivity of coal and salt rock with other common sedimentary rocks can induce subsurface temperature anomalies in the overlying and underlying formations, which can modify the thermal evolution and maturity of the source rocks concerned. This finding is very important for oil and gas resources assessment and exploration and needs further study in detail. The results reported here are representative of the latest and most complete dataset of thermal conductivity of rocks in the Tarim basin, and will provide a solid foundation for geothermal studies in future. 相似文献
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