排序方式： 共有13条查询结果，搜索用时 15 毫秒
1.
在内蒙古大青山地区逆冲推覆构造所截切的英安岩中获得锆石~(207)Pb/~(206)Pb表面年龄加权平均值为1870±19Ma,认为英安岩为华北克拉通古元古代末—新元古代一次裂解事件的产物.同时,据安山岩锆石U-Pb年龄谐和度(102)较好的锆石~(206)Pb/~(238)U表面年龄436±4Ma及英安岩锆石U-Pb年龄谐和度(104)较好的锆石~(206)Pb/~(238)U表面年龄153±2Ma和160±2Ma,表明大青山地区逆冲推覆构造存在构造复活或构造追踪现象。这一认识为大青山地区逆冲推覆构造的研究积累了新的资料,提供了新的研究思路。 相似文献
2.
Climate Dynamics - The El Niño–Southern Oscillation (ENSO) Modoki phenomenon has a substantial influence on regional climate. In this study, the results derived from observational and... 相似文献
3.
4.
5.
6.
美国海岸带自然资源与生态损害评估及修复工作对中国的启示 总被引：1，自引：0，他引：1
海岸带是位于海陆结合部的复杂环境系统,是人类活动最集中的地区。中国大陆海岸线约18000km,涉及沿海11个省,由于经济社会高速发展,海岸带地区的人口、资源、环境矛盾日益突出,面临海岸带资源无序开发、水土污染、滨海湿地退化、海岸侵蚀、地面沉降等一系列生态环境与灾害地质问题,已成为影响生态文明建设的主要问题之一。因此中国持续加大海岸带生态环境保护力度,并提出实施重要生态系统保护和修复重大工程、强化湿地保护和修复等政策措施。美国国家海洋和大气管理局主导的海岸带损害评估及修复计划已实施了近30年,并取得了显著效果,其完善的法律制度体系、规范的损害评估和修复程序、数据集成管理和共享应用等成功经验值得学习借鉴。建议加快完善中国海岸带生态环境损害评估与修复的技术方法体系和制度体系、有序开展海岸带自然资源和生态环境调查、加强海岸带及滨海湿地等重要生态系统的演化和修复技术研究与示范,并构建统一的海岸带基础调查数据库、建立海岸带监测预警体系。 相似文献
7.
大洋科学钻探计划是地球科学领域迄今为止历时最长、成效最大的国际科学合作计划。自1968年以来,先后经历了深海钻探计划、国际大洋钻探计划、综合大洋钻探计划和国际大洋发现计划4个阶段。进入国际大洋发现计划,IODP工作组两次发布科学框架,文章对两个科学框架进行了对比分析。大洋科学钻探的特点和发展趋势是坚持解决重大科学问题,由地球拓展到太阳系,重视技术和大数据,以及扩大社会影响和宣传。这给我国发起国际大科学计划提供了启示,一要注重科技创新,运用大数据等先进技术;二要加强科学管理,促进开放和共享;三要重视提升影响力,扩大宣传和影响。 相似文献
8.
为加快对北极航道和北极地区油气资源的开发利用,保障我国油气能源的持续、稳定和安全供给,文章基于"冰上丝绸之路"的提出和建设,分析我国油气能源战略。研究结果表明:"冰上丝绸之路"利用东北航道,从能源储量、能源运输和能源合作3个方面,为我国油气能源提供战略保障;但同时面临北极地区自然条件恶劣、经济基础和配套设施薄弱、生态和环境特殊以及政治利益错综复杂的挑战;未来我国应制定北极战略、拓展科考领域、加强国际合作和强化科技创新,充分发挥"冰上丝绸之路"的作用,保障油气能源供给。 相似文献
9.
10.
ZHANG Xu LIU Chenglin LI Bing WU Linqiang GUI Herong WANG Ziling ZHANG Zhihui LIANG Dexiu 《《地质学报》英文版》2020,94(2):337-351
The Songliao Basin is one of the most important petroliferous basins in northern China. With a recent gradual decline in conventional oil production in the basin, the exploration and development of unconventional resources are becoming increasingly urgent. The Qingshankou Formation consists of typical Upper Cretaceous continental strata, and represents a promising and practical replacement resource for shale oil in the Songliao Basin. Previous studies have shown that low-mature to mature Qingshankou shale mainly preserves type Ⅰ and type Ⅱ1 organic matter, with relatively high total organic carbon(TOC) content. It is estimated that there is a great potential to explore for shale oil resources in the Qingshankou Formation in this basin. However, not enough systematic research has been conducted on pore characteristics and their main controlling factors in this lacustrine shale reservoir. In this study, 19 Qingshankou shales from two wells drilled in the study area were tested and analyzed for mineral composition, pore distribution and feature evolution using Xray diffraction(XRD), scanning electron microscopy(SEM), low-pressure nitrogen gas adsorption(N2-GA), and thermal simulation experiments. The XRD results show that clay, quartz, and feldspar are the dominant mineral constituents of Qingshankou shale. The clay minerals are mostly illite/smectite mixed layers with a mean content of 83.5%, followed by illite, chlorite, and kaolinite. There are abundant deposits of clay-rich shale in the Qingshankou Formation in the study area, within which many mineral and organic matter pores were observed using SEM. Mineral pores contribute the most to shale porosity;specifically, clay mineral pores and carbonate pores comprise most of the mineral pores in the shale. Among the three types of organic matter pores, type B is more dominant the other two. Pores with diameters greater than 10 nm supply the main pore volume;most are half-open slits and wedge-shaped pores. The total pore volume had no obvious linear relationship with TOC content, but had some degree of positive correlation with the content of quartz + feldspar and clay minerals respectively. However, it was negatively correlated with carbonate mineral content. The specific surface area of the pores is negatively related to TOC content, average pore diameter, and carbonate mineral content. Moreover, it had a somewhat positive correlation with clay mineral content and no clear linear relationship with the content of quartz + feldspar. With increases in maturity, there was also an increase in the number of carbonate mineral dissolution pores and organic matter pores, average pore diameter, and pore volume, whereas there was a decrease in specific surface area of the pores. Generally, the Qingshankou shale is at a low-mature to mature stage with a TOC content of more than 1.0%, and could be as thick as 250 m in the study area. Pores with diameters of more than 10 nm are well-developed in the shale. This research illustrates that there are favorable conditions for shale oil occurrence and enrichment in the Qingshankou shale in the study area. 相似文献