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111.
满洲里国家基准站搬迁至新站后,根据2010年1-12月新旧自动观测站气温、气压、风向风速、相对湿度、地温等气象要素的观测数据,进行整理,用差值分析法进行对比,并从观测环境的改变、拔海高度、下垫面性质、热岛效应等方面揭示影响新旧站的差异因素。 相似文献
112.
Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
113.
文章通过大量岩芯、铸体薄片观察和测井资料分析,对准噶尔腹部石西石炭系火山岩风化壳储层进行了详细地研究。研究结果表明,该火山岩风化壳储层的储集空间主要有基质溶孔、气孔或杏仁体溶孔、角砾间溶孔、微裂缝和裂缝等,其中与裂缝连通的各类溶孔占主导地位;在岩石分布上以集块岩、条带状熔岩、角砾熔岩和致密凝灰岩为主,玄武岩、安山岩和流纹岩则相对较少;储层物性主要表现为高孔低渗,只有裂缝具有较高的渗透率,且裂缝以高角度缝和直立缝为主。研究还发现,岩性岩相、裂缝和风化淋滤作用是影响该风化壳储层的主要因素。区内油层主要聚中在构造高部位、靠近断裂带和有利岩相区域;油层分布在离石炭系风化壳顶面25~150 m的范围内。 相似文献
114.
Over the past 20 years, China has experienced multiple economic transitions characterized by marketization, globalization, decentralization, and urbanization; as a result, urban land development intensity (ULDI) has become a significant issue for sustainable development. As China’s largest globalized urban area, the rapid socio-economic development of the Yangtze River Delta has created a huge demand for urban land. We apply a theoretical framework for a four-dimensional analysis tool to understand the dynamic evolution of the ULDI in the context of economic transition. It reveals that marketization, globalization, decentralization, and urbanization affect the ULDI in the economic transition of Yangtze River Delta. Marketization, especially the continuous improvement of land marketization, optimizes the spatial allocation of land resources and encourages urban land users to improve ULDI. Globalization promotes the rapid growth of economy and population through an increase in foreign direct investment. In the process of decentralization, local governments rely on developing a mode of land finance, resulting in a disordered urban space and low ULDI. Population growth and agglomeration during urbanization stimulates residents’ consumption capacity and promotes economic growth, thus creating a greater demand for urban land. However, a low level of development and utilization restricts the improvement of development intensity. Economic development can improve the level of land-intensive use by promoting the adjustment, optimization, and upgrade of urban industrial structures. 相似文献
115.
提出了一种基于地形变化长波项与短波项相结合的残余误差综合削弱方法。实验验证了该方法的有效性。 相似文献
116.
SONG Huailong 《《地质学报》英文版》2014,88(Z1):196-197
正Salt desert,saline-alkaline dust storm and saline-alkaline mixed dust storm are significant but ignored problems for a long time.After many years of observations and researches,the author believes that salt desert,saline-alkaline dust 相似文献
117.
多年冻土区典型地面浅层地温对降水的响应 总被引:1,自引:0,他引:1
在大气-地面-冻土之间存在复杂的水热变化过程,降水是青藏高原地区主要的水分补给来源,在浅层形成水热变化的不连续层。通过对北麓河地区降水和工程路面(沥青路面、砂砾路面)、天然地面(高寒草原、高寒草甸)浅层(0~80cm)温度数据的原位监测,分析在不同降水量和不同时段浅层的温度变化,结果表明:北麓河地区年降水量逐年增加,增加速率为22.9mma-1。降雨主要集中在5~9月。白天地温对降水的响应比夜间强烈。工程路面夜间的温度变化大于天然地面。在相同降水条件下, 10:00~15:30时段的温度变化量大于16:00~18:00时段。随着降雨量的增加,温度下降幅度增大。砂砾、高寒草原、高寒草甸地面地温对降水的响应深度范围为0~30cm。受路面结构中隔水层的影响,沥青路面为0~20cm,且5cm深度温度的变化幅度大于地表。为进一步研究不同地面类型不同水热传输模式层结的划分提供数据基础。 相似文献
118.
根据矿区勘查和推覆构造研究资料,论述三明吉口矿区煤矿推覆构造特征与控煤作用,认为区内煤系地层为受推覆构造影响的“外来岩系”。以卷入地层及相关的岩体时代分析,认为区内拆离构造和推覆构造分别形成于印支期与燕山早期。 相似文献
119.
Dimitris A. Retalis 《Pure and Applied Geophysics》1977,115(3):575-581
In the present study the influence of smoke and sulfur dioxide concentrations and of wind velocity on the concentration of small positive and negative ions above Athens area (=37°58.3N, =23°43E,h=107 m) is examined.Between the above mentioned elements simple linear correlation and multiple linear correlation is attempted. This correlation is based on mean daily values of the elements, for the two-year period 1971–1972, for each month separately.From the above examination it has been ascertained that small ions concentration increases as smoke and/or sulfur dioxide concentration decreases. Also, small ions concentration increases as wind velocity increases.In addition, it was ascertained that sulfur dioxide contributes the least to the determination of the variance of small ions concentration, whilst the greatest contribution is made by smoke for the positive small ions or by wind velocity for the negative ones. 相似文献
120.
临港新城地质特征及其对新城规划与建设的影响分析 总被引:1,自引:1,他引:1
结合临港新城三维地质调查所取得的成果,分析了该城区地质特征及对新城建设的影响,为新城规划建设提供科学依据和服务。 相似文献