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901.
利用D-InSAR技术,选用汶川地震前日本ALOS/PALSAR数据,提取了汶川地震前4个条带的形变场,形变场覆盖了映秀镇、茂县、北川县、平武和青川县.结果显示,汶川地震前形变场沿断层呈“凸”状对称形变分布特征,沿发震断层附近出现隆起形变,而远离发震断层两盘均出现下沉,且随着远离断层距离的增加,沉降幅度逐步增加.在断层两侧附近的平武、北川、安县、江油一带出现了大面积形变隆起,幅度为5~10 cm,且断层西侧抬升范围大于东侧.在映秀镇和汶川地震震中附近,沿断层两侧呈现出小范围斑块状隆起,范围在10~15 cm.该隆起区域与汶川震中位置和破裂最强烈段落基本一致.在远离断层的两盘区域出现沉降,绵阳至成都一带沉降范围在0~ -10 cm之间,松潘至文县一带沉降范围在-5~ -10 cm之间.研究表明对于处于闭锁阶段的逆冲断层,震前的垂直变形可能是其主要变形特征.虽然获得的震前形变变化可能存在5 cm的DEM和对流层大气延迟造成的误差,但这种震前垂直形变场变化趋势仍然存在,可能为地震监测预报提供科学依据. 相似文献
902.
本文简要地介绍了衍射增强成像方法的物理原理,根据折射角信息提取所需要的DEI图像采样的数量进行分类,分别详细介绍了利用两幅DEI图像、三幅DEI图像以及多幅DEI图像进行折射角信息提取的算法,并依次分析了它们的特点及性能.对于不同的实际应用需要,灵活的选择使用这些折射角信息提取方法,可以获得更好的图像效果. 相似文献
903.
Wagner José Barreto Dilson Norio Ishikawa Ieda Spacino Scarminio João de Souza Costa Paulo dos Santos Nora Miriam de Fatima Soares Romilaine Mansano Nicolau Adriana Celeste Esteves Gonçalves Sonia Regina Giancoli Barreto 《洁净——土壤、空气、水》2008,36(4):353-359
The conservation of large water resources is essential for the preservation of human life. The quantification and, more importantly, the speciation of chemical substances that indicate the presence of anthropogenic contamination in water resources are of great importance. This paper presents the results of analysis for the determination of organic, inorganic and total phosphorus, pseudo‐sulfur, and iron and manganese, in five fractions, in water sediments collected from the Capivara Hydroelectric Power Plant, Brazil. A study on the seasonal variation of these parameters was conducted, with data having been collected in the winter and in the summer, at two sites along the dam, 5 km apart, close to the city of Primeiro de Maio. Phosphorous was found in sediments and adjacent soil in the organic form (OP), and was used as an indicator of anthropogenic influence on the reservoir banks. Speciation of potentially toxic Mn showed that it is present in the exchangeable fraction of the 0–5 cm depth layer (sediment/water interface), making its transfer to the water column possible. Results from this study showed that domestic and industrial effluent treatment measures are needed for the preservation of the quality of aquatic environments. 相似文献
904.
905.
906.
C.-Y. Cynthia Lin 《Natural Resources Research》2009,18(1):19-28
This paper uses annual data on world oil price and consumption from 1965 to 2006 to calibrate a Hotelling model of optimal
nonrenewable resource extraction. Numerical solutions are generated for various specifications of the elasticity of demand
for both isoelastic demand and linear demand under each of two possible market structures: perfect competition and monopoly.
Prior to the 1973 oil crisis, the model that best fits actual data is one of perfect competition with linear demand and a
demand elasticity of −0.4. For the periods 1973–1981 and 1981–1990, the model that best fits actual data is one of monopoly
with linear demand and demand elasticities of −0.8 and −0.7, respectively, suggesting that the market was strongly influenced
by OPEC during this time. Under the model that best fits the most recent period (perfect competition with linear demand and
demand elasticity −0.5), the real oil price (in 1982–1984 U.S.$) should fall in the range $60.87–$66.31/barrel over the years
2010–2030.
相似文献
C.-Y. Cynthia LinEmail: |
907.
新疆旅游资源的类型、等级及空间分布特征 总被引:5,自引:3,他引:2
在全面掌握新疆旅游资源的实查资料基础上,对全疆旅游资源做系统分类与定量评价,总结其类型、等级和空间分布特征,并从新疆地理环境变迁和多民族、多文化的社会环境两方面分析新疆高品质旅游资源的成因。结果表明:新疆旅游资源类型多样,与全国相比,主类、亚类齐全,基本类型占66.5%;八大类中建筑与设施和地文景观的种类较丰富;建筑与设施类景点最多,水域风光和生物景观次之;新疆旅游资源等级较高,优良级占43.6%,整体为中间大两头小的谷仓型结构;高等级集中于凸峰、观光游憩湖区、林地、草地、野生动物栖息地、废城与聚落地、石窟、边境口岸、特色街巷、传统手工产品与制品、民间演艺等类;空间分布呈现为三带两环状和六点状集聚特征,这与新疆地貌格局和高品质景点的聚群作用有关;新疆自然旅游资源是整个地理环境演变过程的产物;而多民族、多文化的社会环境是人文类的主要成因。 相似文献
908.
WANG Shiqin SONG Xianfang WANG Qinxue XIAO Guoqiang LIU Changming LIU Jianrong 《地理学报》2009,19(2):175-188
The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain (NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan. The automatic groundwater sensors were installed for the corporation project between China and Japan. Combined with the monitoring results from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten. According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including discharge pattern in the piedmont plain, lateral recharge– runoff–discharge pattern in the piedmont plain, recharge–discharge pattern in the central channel zone, precipitation infiltration–evaporation pattern in the shallow groundwater region of the central plain, lateral recharge–evaporation pattern in the recharge-affected area along the Yellow River and infiltration–discharge–evaporation pattern in the littoral plain. Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted and the influencing factors of different dynamic patterns were compared. 相似文献
909.
简要介绍了聊古1井井区的水文地质条件,全面调查了聊城地震水化站外围地热资源开发的现状,在此基础上分析了地热开发对地震地下流体观测及其动态的影响。结果表明,井区周围地热开发导致聊古1井断流,引起了各项动态异常的出现;该井区碳酸盐岩岩溶性水的开采对地下流体观测及其动态产生影响,特别是冬季供暖期的开采对地下水物理动态产生严重干扰。为了消除或减弱这种影响,通过改造井口装置实现人工自流的方法,保证了各项观测,而且部分测项的观测条件得到改善,多数测项的动态资料可连续,只有少数测项动态受到较大影响,井口改造取得了一定实效。然而,根本的出路还应是保护观测系统,停止同层地热开发 相似文献
910.