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971.
新场气田是川西的主力产气区,发育深层上三叠统(须家河组二段、须家河组四段)和中浅层中、上侏罗统(上沙溪庙组、蓬莱镇组)含气层系,均不同程度地产出地层水,气水关系复杂,不同层位间气水存在一定的联系。纵向上,深层地层水埋深为3 000~5 500 m,随埋深增加矿化度、盐化系数逐渐增大,呈现高演化地层水特征;中浅层地层水埋深为500~2 200 m,沟通较频繁,水化学特征差异不大,均呈现低矿化度、低盐化系数和高碳酸氢根离子浓度特点;两者之间为地层水混合过渡带。平面上,中浅层上沙溪庙组地层水矿化度在断裂发育带附近出现高值,高值范围与深层须家河组地层水矿化度低值区基本相对应。这主要是由局部深层与中浅层地层水沿向下断至深层、向上断至中浅层的断层垂向沟通并发生混合作用导致的。中浅层断裂附近,沿断裂带上涌的深层地层水与中浅层原始沉积地层水发生混合作用,使得砂体富含高矿化度地层水,天然气则沿渗透性砂体侧向运移并在一定距离的圈闭内聚集成藏,这对研究区中浅层天然勘探具有指导意义。  相似文献   
972.
973.
Zhu  Zhishuang  Zhang  Huaming  Tao  Gege  Yu  Feng 《Natural Hazards》2015,84(1):167-178

Natural gas plays an important role in the mitigation of climate change, yet its development is constrained by the current natural gas pricing mechanism in China. In the context of the natural gas pricing reform, this paper analyzes the potential effects on price level and total output. Through the input–output model, some conclusions are drawn as follows: (1) The gas pricing reform has relatively great impact on the products’ price of the sectors that have large gas consumption, such as industrial sectors and some service sectors, and on the total output of the gas production and supply sectors and the petroleum and natural gas extraction sectors, whereas the reform has relatively small impact on other industries; (2) effects of gas pricing reform on urban and rural residents are dissymmetrical, with larger effects on urban residents and (3) the reform has relatively small impacts on both various price indices and total output levels; thus, the government can realize the promotion of gas pricing reform nationwide at a cost of relatively small increase in general price level and little lose of total output.

  相似文献   
974.
975.
<正>Ophiolites are fragments of ancient ocean lithosphere emplaced on continental margins,in island arcs or in accretionary prisms,and have long been studied to better understand the evolution of ocean basins and collision of tectonic plates,the processes of mountain building and the occurrence of valuable ore bodies,such as podiform  相似文献   
976.
<正>Previously reported in the Mesozonic Tibet and the early Paleozoic Polar Ural,Russia,diamond and other deep minerals are found in ophiolite mantle peridotite chromite that need to be reconsidered ophiolite and chromite traditional understanding of the causes of shallow.The ophiolitic chromitite can be divided two classes,the high-Cr chromitite and high-Al chromitite.  相似文献   
977.
The transition area of three natural zones (Eastern Monsoon Region, Arid Region of Northwest China, Qinghai Tibet Plateau Region) is influenced by the Asian monsoon and middle latitude westerly circulation because of its special geographical position. And it is more sensitive to global climate change. The Koppen climate classification, which is widely used in the world, and the accumulated temperature-dryness classification, which is usually used in China, were used to study the climate zones and changes in the region of longitude 97.5°~108°E, latitude 33°~41.5°N, from 1961 to 2010. The changing areas of each climate zone were compared to the East Asian Summer Monsoon index, the South Asian Summer Monsoon index, the Summer Westerly index, the East Asian Winter Monsoon index, the Plateau Summer Monsoon index, the North Atlantic Oscillation index, the Southern Oscillation index, NINO3.4 index, to explore the response of the transition area of three natural zones to each climate system. According to the results, this region will become wetter when the Summer Westerly or the East Asian Winter Monsoon is relatively strong. When the East Asian Summer Monsoon or the South Asian Summer Monsoon becomes strong, the climate in low altitude region of the study area will easily become drier, and the climate in high altitude region of the study area is easily to become wetter. When the Plateau Summer Monsoon is relatively strong, the climate in the study area will easily become drier. When the North Atlantic Oscillation is relatively strong, the study area will easily become wetter. And when the El Niño is relatively strong, or the Southern Oscillation is relatively weak, the study area will easily become drier. In general, the moisture status of this region is mainly controlled by the middle latitude westerly circulation. The enhancement of the Asian summer monsoon could increase the precipitation in the southeast part of this regional, but, according to the degrees of dryness and the types of climate change in this paper, warming effects could offset precipitation increasing and make the area drier. The transition area of three natural zones is influenced by multiple interactions of climate systems from East Asia. A single climatic index, such as air temperature or precipitation, can not completely represent the regional features of climate change. As a result, areas of climate zones can be used as an important index in the regional climate change assessment.  相似文献   
978.
979.
地球科学大数据的到来,迫切需要通过地球数据科学系统对地学数据机理、采集处理、存储管理,特别是集成共享与挖掘分析等进行研究,以便通过大数据资源,发现和揭示数据背后隐含的地学规律和知识,促进地学科技创新。本文首先分析了地球数据科学的内涵特征,提出了地球数据科学的基础理论方法和技术体系。然后基于国家地球系统科学数据共享实践,重点研究了大数据时代下,面向地球数据科学的地学数据共享新发展。  相似文献   
980.
针对贵州省山地居多、生态环境脆弱、交通通讯不发达,人力资金相对不足等现状,研究建设了在线、离线相结合,内业、外业相协同,"省、市、县、乡"四级一体化应用,涵盖"线索发现、问题分析、外业核查、立案查处"全流程的国土资源执法监察监管系统。系统突破了高效、高精度、多模式的国土资源执法监察监管的系列关键技术方法,建立了国土资源监察监管系统与"一张图"平台一体化集成应用的新模式,已经部署应用到贵州省国土资源执法局和9个市州国土局和若干区县国土局。实践表明系统可以节省大量的国土资源执法人力、物力和时间,有效提升贵州省国土资源执法监察监管的效率和水平。  相似文献   
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