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51.
The research area is situated in the western part of Tarim basin,which includes Awati depression and Bachu uplifted block. It underwent three times processes of compression in a large scale and a near term extension since Cambrian. The first compression occurred during Middle Cambrian to Devonian, which formed fault band folds in NW axial direction. They were "under-water uplift"and distributed all over the research area. The second compression occurred in Late Permian and formed fault band folds and a few fault propagation folds in NS axial direction. They are developed near Tumuxiuke fault belt and the northern research area. The western anticline is bigger than the eastern one in extent and size. The third compression occurred during Palaeogene to Quaternary and formed tumuxiuke fault belt and fault propagation folds in NW direction. They are distributed over the south part of the research area. Tumuxiuke fault belt is a big scale dextral reversed strike-slip fault belt; it transformed or destroyed the fold structure of the research area. A short-term extension occurred during Early Permian. Tarim Basin is in the rift forming stage of craton, and there exist widespread basic volcanic rocks, basic intrusive bodies and dikes.  相似文献   
52.
根据1999年竣工的南四湖清障工程实施前后的水文观测资料,从湖区水面比降、洪水落平时间等要素的变化,进行了湖区行洪分析。通过分析发现:工程的实施,降低了卡口段的水位,减小了工程位置以下的湖区水面比降,缩短了湖区行洪时间,加快了洪水宣泄,使入湖河道洪水尽快下泄,提高了湖区行洪能力,分析成果对南四湖防洪调度以及进一步做好湖内清障工程,具有重要的参考价值。  相似文献   
53.
塔里木盆地西部地区主要石油地质特征及油气远景   总被引:3,自引:1,他引:2       下载免费PDF全文
研究区构造上属中央隆起的巴楚断隆东北部和北部坳陷的阿瓦提凹陷南部。文章详细剖析了烃源岩的时代和类型,提出寒武-奥陶系的暗色泥岩、碳酸盐岩和石炭系的暗色泥岩、碳酸盐岩是区内的两套主要烃源岩。在论述了储集条件(7大套好或中等储层)、保存条件(10套Ⅰ类和Ⅱ类盖层)、生储盖组合形成(5套储盖组合)和吐木休克断裂活动(两期重大的冲断活动)的基础上,认为该区的油气藏形成时期主要受控于储盖组合形成期、圈闭形成期和排烃期,因而本区的主要成藏期是二叠纪末和新近纪。据此对研究区的油气远景进行了评价,提出和田河下游断鼻构造带和巴东4井区背冲构造是近期的勘探靶区。  相似文献   
54.
基于中国在推进以“人”为核心的新型城镇化过程中人口、资源、环境与经济、社会发展诸要素相互促进或相互制约的复杂关系视角,借鉴人口承载力思想,提出区域PRED系统承载力概念及其表征方法,参考压力—状态—响应模型(PSR),构建了区域PRED系统的承载力—压力—状态—响应评价指标体系(CPSR 模型),在此基础上提出区域PRED系统综合响应度与应急响应级别划分标准,通过多目标规划与决策方法对区域PRED系统进行综合评价。以2000-2012 年大连市PRED系统为例进行实证分析,结果显示:① 研究时段内大连市PRED系统一直处于超载状态,人口承载力由363 万人降至291 万人;② 大连市PRED系统压力低于全国平均水平,区域PRED系统负荷指数由0.97 降至0.85,区域PRED系统综合响应级别始终处于Ⅱ级橙色预警或Ⅲ级黄色预警状态。评价结果基本符合近年来大连市有关资源、环境及经济、社会发展的客观实际,评价结果可视性较强、可靠性较高。区域PRED系统承载力概念以及基于CPSR模型的区域PRED系统综合评价指标体系、多目标决策评价方法,为定量评价区域可持续发展提供了一种新的思路和方法,对新型城镇化背景下的相关政策制定具有一定参考价值。  相似文献   
55.
Based on provincial panel data of water footprint and grey water footprint, and with the help of data envelopment analysis model considering and without considering the unde- sirable output, this paper estimates the water resources utilization efficiency in China from 1997 to 2011. The spatial weighting matrix based on economy-spatial distance function is established to discuss spatial autocorrelation of water resources utilization efficiency. With the help of absolute/3-convergence model, this paper concludes that there exists/%convergence in the water resources utilization efficiency. Under the conditions of considering and without considering the undesirable output, it takes about 52.6 and 5.6 years respectively to achieve the extent of half of convergence. By mean of the spatial Durbin econometric model, this paper studies spatial spillover effects of the provincial water resources utilization efficiency in China. The results are as follows. 1) With considering and without considering the undesir- able output, there is significant spatial correlation in provincial water resource efficiency in China. 2) Under the two cases, the spatial autoregressive coefficients (p) are 0.278 and 0.507 respectively, at 1% significance level. There exist the spatial spillover effects of provin- cial water resources utilization efficiency. 3) With considering the undesirable output, these factors of the education funds, the transportation infrastructure, and the industrial and agri- cultural water consumption proportion have positive impacts. These factors of foreign direct investment, the industry value-added water consumption per ten thousand yuan, per capita water consumption, and the total precipitation have negative impacts. 4) Without considering the undesirable output, the factor of GDP per laborer has a greater positive significant influ- ence on the water resources utilization efficiency. However the facts of industry value-added water consumption in ten thousand yuan and the transportation infrastructure have no sig- nificant influence. 5) Regardless of undesirable output of water resources utilization efficiency the assessment of the present real water resources utilization in China will be distorted and policy-making will be misled. The water efficiency measure considering environmental factors (such as gray water footprint) is more reasonable.  相似文献   
56.
Based on the synergetic development of new industrialization, rapid urbanization and agricultural modernization (IUAM), and from the viewpoint of interactive relationships between water resources and regional population, eco-environment, economy and society, the concepts of water resources intensity (WRI), water environment intensity (WEI), water resources relative efficiency (WRRE) and water environment relative efficiency (WERE) are defined with reference to energy intensity, resources efficiency and environment efficiency theory. On the basis of benchmarking theory, the quantitative characterization and evaluation method of “Three Red Lines” (the upper limit of water resources allocation, the baseline of utilization efficiency of water resources and the upper limit of sewage discharge) is proposed. According to these concepts and models, an empirical analysis of the Three Red Lines of water resources on the Chinese mainland between 2003 and 2012 was carried out. The results showed that total water consumption in eastern, central and western parts of China possesses “club convergence” characteristics, which means these areas have similar internal conditions appeared convergence in the development. Inter-provincial differences in water consumption continue to decrease, but the north–south differentiation characteristics in the eastern and central regions were still relatively obvious, while provincial differences in the eastern part were at a minimum and the central region had the largest. Water Resources Efficiency (WRE) of all four sectors in the Southwest rivers and Huaihe River basins were generally high. Industrial WRRE in the Songhua River, Yangtze River and Pearl River basins, agricultural WRRE in the Songhua River, Yellow River and northwestern river basins and domestic WRRE in the Liaohe River, Yangtze River and Pearl River basins were all low. Eco-environmental WRRE in the southeastern rivers and Yangtze River basins were low but showed an upward trend. Other river basins, except for the Northwestern rivers basin, had high eco-environmental WRRE with a downward trend. Western China, especially the northwestern part, had a low relative intensity of the water environment (WERI) and high integrated water environment management (IWEM) performance, but the relative intensities of the water resources (WRRI) were fairly high, and the comprehensive performance of integrated water resources management (IWRM) in these regions was low. In southern China, especially the southeastern part, the IWEM was fairly high, but the overall IWRM was lower.  相似文献   
57.
基于生态系统服务理论界定生态福祉概念及其表征、评价方法,借鉴资源诅咒理论,提出广义生态福祉视域下的生态祝福及生态诅咒假说,结合有关年度统计数据、以中国大陆地区为例展开实证分析。结果表明:① 从人均生态福祉来看,全国范围内的绝对生态诅咒假设不成立,东、西部地区生态祝福效应显著;② 从农林牧渔产业从业人员比例来看,全国及地区层面的条件生态诅咒假设均不成立,东部地区生态祝福效应显著;③ 从农林牧渔产业产值比例来看,全国及地区层面的条件生态诅咒假设均显著成立。自然生态系统为提高区域人均生态福祉、吸纳富余劳动力就业等贡献显著,但促进地区经济社会发展还需不断降低农林牧渔产业产值在国民经济中的比例。未来,中国应当进一步实施因地制宜的生态保护措施以规避生态诅咒,并通过因时制宜的经济社会发展规划促进生态祝福效应。  相似文献   
58.
2005年7月25日23点43分在黑龙江省林甸县发生了Ms5.1地震.据黑龙江省地震台网测定,这次地震的震中位置为北纬46°56'、东经124`54'.根据大庆地震台网记录结果,至2005年12月30日24时止,大庆林甸5.1级地震序列共发生余震88次,最大余震为7月25日23时57分ML4.0地震.其中不可定位地震56次,ML0.1-0.9地震1次,ML1.0-1.9地震18次,ML2.0-2.9地震7次,ML3.0-3.9地震4次,ML4.0-4.9地震1次.  相似文献   
59.
本文较系统地介绍了绢云母矿区地质概况和矿床地质特征,并通过成因矿物学论述,对矿床成因机理进行了探讨分析,指出了下一步的找矿方向.  相似文献   
60.
The Songliao basin (SB) is a superposed basin with two different kinds of basin fills. The lower one is characterized by a fault-bounded volcanogenic succession comprising of intercalated volcanic, pyroclastic and epiclastic rocks. The volcanic rocks, dating from 110 Ma to 130 Ma, are of geochemically active continental margin type. Fast northward migration of the SB block occurred during the major episodes of the volcanism inferred from their paleomagnetic information. The upper one of the basin fill is dominated by non-marine sag-style sedimentary sequence of siliciclastics and minor carbonates. The basin center shifted westwards from the early to late Cretaceous revealed by the GGT seismic velocity structure suggesting dynamic change in the basin evolution. Thus, a superposed basin model is proposed. Evolution of the SB involves three periods including (1) Alptian and pre-Aptian: a retroarc basin and range system of Andes type related to Mongolia-Okhotsk collisional belt (MOCB); (2) Albian to Companian: a sag-like strike-slip basin under transtension related to oblique subduction of the Pacific plate along the eastern margin of the Eurasian plate; (3) since Maastrichtian: a tectonic inverse basin under compression related to normal subduction of the Pacific plate under the Eurasian plate, characterized by overthrust, westward migration of the depocenter and eastward uplifting of the basin margin.  相似文献   
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