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81.
基于C30重排藿烷(C30DH)和C30藿烷(C30H)热稳定性差异,研究了C30DH/C30H作为油气运移方向和充注途径的可行性.结果发现:C30DH结构稳定性高于C30H,C30DH/C30H参数具有成熟度属性;同时对比分析C30DH/C30H参数与咔唑类参数的相关性,认为两者之间正相关性明显,表明C30DH/C30H参数不仅是良好的热成熟度参数还是良好的石油充注运移参数.M油田位于Fula凹陷东部,M油田原油为弱氧化-还原、淡水-微咸水环境下低等藻类与高等植物混源生成,属于同一族群原油.利用C30DH/C30H参数示踪Fula凹陷M油田石油充注方向,油气运移途径主要为自北向南,同时还发育自西向东的运移途径;咔唑类参数也验证了C30DH/C30H参数示踪油气运移的准确性.结果表明C30DH/C30H参数是示踪石油充注途径的有效参数. 相似文献
82.
应用地球化学元素、地球化学淋溶系数及环境温度指标,研究了北极阿拉斯加巴罗热融湖Ikroavik钻孔岩芯AB-32连续的高分辨环境记录。结合210Pb测年数据,指出巴罗地区气候、环境变化的历史状况是:1600~1735年为寒冷、干燥时期;1750~1830年,气候变暖、变湿;1830年出现明显的地球化学转折界限,1830~1994年,气候较湿润温暖。1969~1970年前后,巴罗地区有一变冷阶段。AB-32钻孔岩芯1830年左右表现的古地球化学特征与现代Ikroavik湖泊环境地球化学特征相吻合,并且和Elson泻湖AB-67沉积岩芯反映的气候环境变化基本一致。 相似文献
83.
84.
Zhe Yang Shuli Song Wenhai Jiao Guangming Chen Junchen Xue Weili Zhou Wenyao Zhu 《GPS Solutions》2017,21(2):363-375
This study carries out a quantitative analysis of the performance of ionospheric tomography in the topside ionosphere, utilizing data of October 2011 collected from 260 Global Navigation Satellite System (GNSS) stations in the Crustal Movement Observation Network of China. This tomographic reconstruction with a resolution of 2° in latitude, 2° in longitude and 20 km in altitude has more than 70 % of voxels traversed by GPS raypaths and is able to provide reliable bottom parts of ionospheric profiles. Compared with the observations measured by the Defense Meteorological Satellite Program (DMSP) satellites (F16, F17 and F18) at an altitude of 830–880 km, the results show that there is an overestimation in the reconstructed plasma density at the DMSP altitude, and the reconstruction is better during daytime than nighttime. In addition, the reconstruction at nighttime also indicates a solar activity and latitudinal dependence. In summary, with respect to DMSP measurements, the daytime bias is on average from ?0.32 × 105/cm3 to ?0.28 × 105/cm3, while the nighttime bias is between ?0.37 × 105/cm3 and ?0.24 × 105/cm3, and the standard deviation at daytime and at nighttime is, respectively, 0.082 × 105/cm3 to 0.244 × 105/cm3 and 0.086 × 105/cm3 to 0.428 × 105/cm3. This study suggests that vertical ionospheric profiles from other sources, such as ionosondes or GNSS occultation satellites, should be incorporated into ground-based GNSS topside tomographic studies. 相似文献
85.
86.
Effects of antecedent soil moisture on losses of rare earth elements and phosphorus in runoff 总被引:1,自引:1,他引:0
Lingqing Wang Tao Liang Weili Wang Chaosheng Zhang 《Environmental Earth Sciences》2012,66(8):2379-2385
The effects of antecedent soil moisture on losses of rare earth elements (REEs) and phosphorus (P) in runoff were evaluated through a simulated rainfall experiment at the rate of 83?mm?h?1. The results revealed that antecedent moisture was a significant factor affecting the amounts of REE and P losses. It was observed that most REEs and P transported with sediments in the runoff. There was a significant correlation between the total amounts of REE losses and those of P losses in the runoff. The optimal antecedent moisture for minimization of losses for REEs ranged from 10.19 to 11.17% and it was 10.91% for P. 相似文献
87.
The existence of three well-defined tongue-shaped zones of swell dominance, termed as ‘swell pools’, in the Pacific, the Atlantic
and the Indian Oceans, was reported by Chen et al. (2002) using satellite data. In this paper, the ECMWF Re-analyses wind wave data, including wind speed, significant wave
height, averaged wave period and direction, are applied to verify the existence of these swell pools. The swell indices calculated
from wave height, wave age and correlation coefficient are used to identify swell events. The wave age swell index can be
more appropriately related to physical processes compared to the other two swell indices. Based on the ECMWF data the swell
pools in the Pacific and the Atlantic Oceans are confirmed, but the expected swell pool in the Indian Ocean is not pronounced.
The seasonal variations of global and hemispherical swell indices are investigated, and the argument that swells in the pools
seemed to originate mostly from the winter hemisphere is supported by the seasonal variation of the averaged wave direction.
The northward bending of the swell pools in the Pacific and the Atlantic Oceans in summer is not revealed by the ECMWF data.
The swell pool in the Indian Ocean and the summer northward bending of the swell pools in the Pacific and the Atlantic Oceans
need to be further verified by other datasets. 相似文献
88.
Jinhua Pan Xin Jiang Xiaojie Li Yizhou Cong Zhuangzhi Zhang Zhiling Li Weili Zhou Houwei Han Shiju Luo Guanpin Yang 《中国海洋大学学报(英文版)》2011,10(2):147-152
Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive
research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially
useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination
to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination
rate of eelgrass (Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45,
increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA)
(P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly
increased the germination rate at salinity 5 (P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination
rate at 14°C (P<0.001). Although significant interaction was found between temperature and salinity (P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results
provide useful information for the propagation of artificial seedlings for seagrass restoration in China. 相似文献
89.
选取大同地震台记录的2010—2019年531个MS≥5.0地震事件,根据发震区域的不同对其波形走时残差进行分析,得到不同发震区域地震波形的平均走时残差。结果表明,日本、喜马拉雅地区地震波形的走时残差总体为负值,平均残差分别为-1.51 s、-0.70 s;斐济、中国台湾地区、南美洲西海岸地区大多为正值,平均残差为0.79 s、1.83 s、1.86 s。同时发现,在有干扰的情况下参考不同区域平均走时残差计算结果,通过判断实际初至震相与理论初至震相的位置关系,可以更好地开展初至波震相识别工作。 相似文献
90.