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61.
二叠纪—三叠纪古气候研究进展——泛大陆巨型季风气候:形成、发展与衰退 总被引:2,自引:0,他引:2
巨型季风是指二叠纪—三叠纪期间泛大陆上存在的强烈季节风,它的形成与泛大陆的形状、海陆分布及大陆的纬向分布密切相关。从晚石炭世泛大陆的聚合至晚侏罗世—早白垩世泛大陆裂解,巨型季风经历了形成、发展到衰退的过程。在三叠纪,泛大陆很大且几乎关于赤道对称,巨型季风达到最大强度。它对古气候、古环境、古生物及沉积等都产生了深刻的影响,使泛大陆低纬度地区呈现出干旱和潮湿交替的气候特征,蒸发岩和红层广泛分布;高纬度地区温暖潮湿,煤层大量分布;科罗拉多高原(美国西部)、西特提斯(欧洲)和东特提斯(中国)等地的二叠纪—三叠纪沉积地层也显示了受巨型季风影响的特征。 相似文献
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The relationship between economic development and energy consumption is revealed by employing cointegration theory, the index decomposition method, and a log-linear regression approach based on a case study of Jilin Province, China. The results suggest: 1) the economic development and energy consumption are interdetermined, whose relationship is positive and long-term. The economic development is highly depending on the energy in Jilin Province. 2) Under the condition of other unchanged factors, the change of industrial energy efficiency contributes to the energy saving, while that of industrial structure increases the energy consumption. 3) The industrial structure change enhances the energy intensity, but the energy utility efficiency change lowers it. From the view of contribution to the energy consumption, the contribution of industrial structure was more than that of the energy utility efficiency in 2000-2011. 4) In 2000-2011, the comprehensive energy intensity change and hydroelectricity energy intensity change were related to all industrial structures' change, and the influencing factors about structure of oil energy intensity change were more than those of coal energy intensity change; from the impact degree, agricultural proportion decreased exerted an positive and greater effect on lowering the energy intensity of comprehensive energy and hydroelectricity, and industrial one did on coal and natural gas. Some conclusions can be drawn as follows: the major way to promote the coordinated development of the industrial economy and energy consumption is to optimize the industrial structure by increasing the proportion of the tertiary industry and low energy consumption industrial sectors and to enhance the energy utility efficiency. 相似文献
64.
老工业区产业结构转型与用地结构转型互动机制及优化路径——以上海市宝山区为例 总被引:1,自引:0,他引:1
尝试理清老工业区产业结构转型与用地结构转型内涵,提出其转型效率的函数表达,分析二者间的互动关系;并运用改进的动态变化度及偏离系数,对上海市宝山区进行实证研究。结果表明:(1)宝山区产业结构与用地结构变化度逐渐增加,工业和第三产业动态度分别由1996年的2.48%和5.36%上升至2012年的4.75%和5.51%,用地结构动态度由11.16%上升至13.53%;(2)宝山区三次产业结构总体趋于优化,但产业内部并未优化,仍以重化工业和传统服务业为主导;(3)宝山区用地结构与产业结构不协调并处于加剧的状态。老工业区产业结构与用地结构存在较强的互动关系,改进的动态变化度及偏离系数方法为老工业区产业结构转型与用地结构转型问题提供了一种研究思路。提出宝山区产业结构转型与用地结构转型的优化路径。 相似文献
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本研究分别在平潭青峰、坛南湾和闽江口琅岐岛采集18个老红砂样品、19个海滩砂样品以及40个河滩砂样品,并对这些样品进行粒度和稀土元素(REE)测量。结果发现老红砂与闽江口琅岐岛河口砂的稀土元素含量特征十分接近;分别对老红砂与闽江河口砂REE数据以及坛南湾海滩砂与闽江口砂(REE)进行了判别函数分析,老红砂的∑REE平均值为84.25μg/g,琅岐岛河口砂的∑REE平均值为89.81μg/g,相似性明显;坛南湾海滩砂的∑REE平均值为16.41μg/g,与闽江河口砂含量差别较大。研究表明:青峰老红砂沉积物主要来源于闽江口河口砂,末次间冰期暖湿气候下闽江输砂量增大,河口外沿岸流增强,大量河砂进入海坛海峡,在强劲的季风搬运下,沉积于平潭岛北部,形成以青峰为代表的平潭岛北部老红砂;而坛南湾海滩砂代表海洋波浪搬运的泥沙,不是老红砂的物源。 相似文献
66.
The retreat of the Tethys Sea and the uplift of the Tibetan Plateau play the critical roles in driving Asian climatic changes during the Cenozoic. In the Pamir–Tien Shan convergence zone, over 3000 m of Cenozoic successions, consisting of marine deposits in the lower, continental clay and fine sand in the middle, and molasse in the upper part, record the evolution of the Tethys Sea, the Asian aridification, and the deformation of the Pamir. In this work, the existing biostratigraphic subdivisions and new electronic spinning resonance dating results were used to assign ages to formations within the Ulugqat section. Sedimentary facies analysis and multi-proxy indices were used to reconstruct the paleo-environmental evolution. The results show: (1) the Pamir–Tien Shan convergence zone has undergone progressive environmental changes from shallow marine before ∼34 Ma to arid land at ∼23 Ma and finally to inter-mountain basin by ∼5.3 Ma; (2) the overall increase in mean size of grains, decrease in redness, in magnetic susceptibility, and in proportion of the ultrafine component of the sediments studied revealed a long-term strengthening in potential energy to transporting medium, cooling, and enhanced continental aridity, respectively; (3) the easternmost edge of the Tethys Sea prevailed in the western Tarim Basin from late Cretaceous to early Cenozoic, and finally retreated from this region around the Eocene–Oligocene transition, which in turn strengthened the Asian aridification; (4) accumulation of molasse with an upper age of ∼1 Ma suggests that the deformation front of the Pamir migrated to this area at or before that time. 相似文献
67.
Luc G. Bulot Jean-Louis Latil Alex Hairabian Arnaud Fournillon 《Proceedings of the Geologists' Association. Geologists' Association》2014
Nolaniceras nolani ( Seunes, 1887) has been widely quoted in the Upper Aptian literature over the years. Re-examination of the holotype of the species shows that it has always been misidentified and that this taxon is represented by a single specimen, the holotype, of uncertain age. As a consequence, its use as an index species for the Upper Aptian should be reconsidered and abandoned. 相似文献
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黄韬 《测绘与空间地理信息》2014,(7):87-88,91
"三旧"改造是国土资源部与广东省联合开展的部省合作,推进节约、集约用地试点示范省工作的重要措施,"三旧"改造地块标图建库为"三旧"改造顺利实施提供数据支撑。本文主要介绍了利用ArcGIS软件ModelBuilder建模功能制作检查和统计工具,快速准确地对广东省"三旧"改造地块标图建库成果进行检查和统计的案例和经验。 相似文献
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