Science and Technology of Delimitation of Continental Shelf and Its Application in Maritime Silk Road Cooperation*     

Qiuci Sun  Yinxia Fang  Jiabiao Li 《地球科学进展》2018,33(12):1215-1222

Delimitation of the continental shelf is an emerging interdisciplinary discipline in the field of international marine science and technology. It uses the scientific and technological means to expand the jurisdiction of coastal states based on the international rules of the 《United Nations Convention on the Law of the Sea》. Therefore, it is related to the marine sovereignty rights and interests of a country and also a hot topic of science and technology that all countries have competed to develop. China has launched the research in this field simultaneously with the world's maritime powers, and formed its innovative advantages in such aspects as geological models, detection techniques and delimitation systems in the delimitation of continental shelf, which have become the brand new ties for China's cooperation with foreign countries in marine science and technology, and also the important field in the maritime silk road cooperation in the 21^st century. This paper introduced the basic principles and methods in the delimitation of continental shelf beyond 200 nautical miles (370 km), progress in the delimitation of the global continental shelf, and China's innovative science and technology as well as its application in maritime Silk Road cooperation, and provided the prospect of the future scientific and technological cooperation with foreign countries and development in this filed. And it was suggested China should develop the scientific and technological cooperation on the delimitation of the continental shelf along the Silk Road, promote the scientific and technological development of the delimitation of the continental shelf in China, and enhance China's influence and voice in international ocean affairs.  相似文献   

青海东昆仑东段加当橄榄辉长岩锆石U-Pb年代学、地球化学及地质意义     

孔会磊  李金超  栗亚芝  贾群子  国显正  张斌 《地质学报》2018,92(5):964-978

东昆仑古特提斯域镁铁—超镁铁质岩石的研究极为薄弱,对青海东昆仑东段加当橄榄辉长岩进行岩相学、年代学和地球化学分析,以期为东昆仑晚古生代—早中生代构造岩浆演化提供新的约束。利用LA-ICPMS锆石U-Pb定年技术,获得橄榄辉长岩加权平均年龄为249.7±3.0Ma(n=21,MSWD=0.105),表明岩体形成时代为早三叠世。岩石地球化学研究表明,加当橄榄辉长岩具有高Al_2O_3(14.71%~18.60%)、低TiO_2(0.07%~0.19%)、贫P2O5(0.02%)、低碱(K_2O+Na_2O=1.65%~2.01%)及Na_2OK_2O的特征,属亚碱性辉长岩。岩石微量元素总体上富集大离子亲石元素(LILE:Rb、Sr、Ba、Th、K)和Pb,相对亏损高场强元素(HFSE:Nb、Ta、P、Zr、Ti),稀土元素总量较低,ΣREE=9.79×10~(-6)~12.55×10~(-6),(La/Yb)N为5.61~28.51,平均11.43,显示轻稀土富集的特征,δEu=1.64~2.48,具有明显的Eu正异常。根据地球化学特征和微量元素判别图解,橄榄辉长岩源区为被俯冲改造的岩石圈幔源岩浆,岩浆在演化过程中遭受了上地壳物质的同化混染,并经历了一定程度的结晶分异作用。结合东昆仑区域构造演化,认为加当橄榄辉长岩是早三叠世阿尼玛卿古特提斯洋北向俯冲阶段岩浆活动的产物。  相似文献   

Spatial and temporal geochemical variability in lacustrine sedimentation in the East African Rift System: Evidence from the Kenya Rift and regional analyses     

《Sedimentology》2018,65(5):1697-1730

Many previous studies on lacustrine basins in the East African Rift System have directed their attention to climatic controls on contemporary sedimentation or climate change as part of palaeoenvironmental reconstruction. In contrast, this research focuses on the impact of tectonism and volcanism on rift deposition and develops models that help to explain their roles and relative importance. The study focuses on the spatial and temporal variability in bulk sediment geochemistry from a diverse range of modern and ancient rift sediments through an analysis of 519 samples and 50 major and trace elements. The basins examined variously include, or have contained, wetlands and/or shallow to deep, fresh to hypersaline lakes. Substantial spatial variability is documented for Holocene to modern deposits in lakes Turkana, Baringo, Bogoria, Magadi and Malawi. Mio‐Pleistocene sediments in the Central Kenya Rift and Quaternary deposits of the southern Kenya Rift illustrate temporal variability. Tectonic and volcanic controls on geochemical variability are explained in terms of: (i) primary controlling factors (faulting, subsidence, uplift, volcanism, magma evolution and antecedent lithologies and landscapes); (ii) secondary controls (bedrock types, rift shoulder and axis elevations, accommodation space, meteoric and hydrothermal fluids and mantle CO ₂); and (iii) response factors (catchment area size, orographic rains, rain shadows, vegetation densities, erosion and weathering rates, and spring/runoff ratios). The models developed have, in turn, important implications for palaeoenvironmental interpretation in other depositional basins.  相似文献   

黔东松桃地区燕山期构造特征研究——以高地超大型锰矿床为例   总被引：2，自引：0，他引：2  

谢小峰  杨坤光  钱山  袁良军 《地质论评》2018,64(3):623-632

黔东松桃地区构造格局主要是受到燕山运动影响形成。燕山早期,区内处于SEE—NWW向区域挤压收缩,形成了NNE—SSW向褶皱和断裂。下寒武统杷榔组—变马冲组地层和南华系下统大塘坡组地层作为两套滑脱层,在构造变形过程中起到滑脱作用,滑脱层内褶皱变形强烈,以大量紧闭、顶厚不协调褶皱为主要构造样式,而其上、下岩层则以断块或宽缓褶皱变形为主,以软弱层为界面,其上、下岩层发生逆冲滑脱作用,形成了区内隔槽式褶皱的构造样式。燕山晚期,区内处于NNE—SSW挤压为主,形成了区内NWW向小型褶皱和断裂,同时燕山晚期构造横跨叠加在早期变形之上,导致早期NNE向褶皱枢纽呈波状起伏,轴迹弯曲,部分地区形成了构造穹窿和构造盆地,部分早期断层呈左行走滑性质。在燕山早、晚两期构造作用下,高地矿区含锰岩系作为软弱滑脱层,向猴子坳向斜的核部进行滑脱聚集,使其在向斜的核部富集,翼部相对减薄。同时,由于犁式正断层的存在,也影响了锰矿层的保存与破坏。  相似文献   

阿尔金山东段阿克塞蛇绿岩地质地球化学特征及形成时代     

王军  李小强  梁明宏  王玉玺  张兵兵  潘保田 《地质通报》2018,37(4):559-569

北阿尔金蛇绿岩带是分布在阿尔金山北缘的一条蛇绿混杂岩带,超基性蛇纹岩岩块、基性岩墙、辉长岩块及基性熔岩组合是该带东段阿克塞蛇绿岩的典型组合形式。地球化学研究结果显示,阿克塞蛇绿岩超基性蛇纹岩以富MgO、贫Al_2O_3、P_2O_5、CaO和K_2O为特征,球粒陨石标准化稀土元素配分曲线表现较平缓,比值接近于1;基性熔岩类中TiO_2为0.86%～1.80%,Al_2O_3为12.00%～14.85%,CaO介于4.89%～19.23%之间,球粒陨石标准化稀土元素配分型式表现为右倾;基性岩墙中TiO_2介于1.08%～2.44%之间,Al_2O_3含量为11.07%～13.26%,Na_2O(1.20%～2.28%)K_2O(0.80%～1.38%),稀土元素总量介于48.65×10~(-6)～124.04×10~(-6)之间,平均92.95×10~(-6);轻、重稀土元素比值介于2.22～4.45之间,总体表现为大洋中脊环境,LA-ICP-MS锆石U-Pb年龄显示,阿克塞蛇绿岩形成于514.6±8.8Ma,为寒武纪,表明在早古生代北阿尔金洋已完全打开,并连通了红柳沟—阿克塞。  相似文献   

东昆仑阿克楚克塞地区辉长岩地球化学特征、锆石U-Pb年龄及其构造意义     

杨锡铭  孙丰月  赵拓飞  刘金龙  彭勃 《地质通报》2018,37(10):1842-1852

东昆仑地区基性-超基性岩石的研究较薄弱,缺乏对东昆仑幔源岩浆活动及岩浆演化的整体认识。对阿克楚克塞辉长岩进行了地球化学、锆石U-Pb年代学及Hf同位素研究,结果显示,该岩石形成于晚三叠世早期(219.3±1.1Ma,MSWD=0.80);岩石SiO2含量为49.03%~57.26%,Mg#值为49~57,属于钙碱性系列岩石;稀土元素配分曲线为轻稀土元素富集的右倾型,富集大离子亲石元素Rb、Ba、K,相对亏损高场强元素Nb、Ta、Ti;εHf(t)=-1.81~3.25,锆石Hf模式年龄大于锆石结晶年龄。地球化学特征显示,阿克楚克塞辉长岩岩浆源区应为受俯冲板片流体交代的岩石圈地幔。结合区域构造背景分析,阿克楚克塞辉长岩形成于印支期造山后伸展的构造环境,继承了早期板片俯冲改造的地幔源区特征。  相似文献   

浅析现浇板裂缝产生原因及治理方法     

李功保 《安徽地质》2005,15(3):225-226

近年来,随着现浇结构使用越来越广泛,但建设物现浇板板角出现裂缝的现象越来越多,笔者就板角裂缝的形成原因,进行了简要分析,并提出了其预防措施.  相似文献   

高空西北气流下铜仁东部特大暴雨的预报分析及思考          下载免费PDF全文

徐大红  胡萍  杨群  李习瑾 《中低纬山地气象》2022,46(2):9-17

利用贵州省预报业务常规、地面自动站加密观测资料、NCEP/FNL1°×1°再分析资料、业务数值预报模式,分析2020年6月29日铜仁市东部高空西北气流影响下的特大暴雨环境场特征、地面中小尺度场特征以及3家数值预报模式检验,初步分析产生此次特大暴雨的可能成因是在副高东南退、东北冷涡槽后高空西北气流维持、低层冷平流下传西输、地面辐合维持增强为涡旋、地面东路弱冷空气侵入、能量锋区斜压性增强;短临监测发现雷达回波有列车效应、低层辐合高层辐散的共轭配置、中层气旋式辐合;初步得出了西北气流影响下弱天气尺度环境场的铜仁市东部暴雨的预报着眼点。  相似文献   

Dominant Modes of Interannual Variability in Atmospheric Water Vapor Content over East Asia during Winter and Their Associated Mechanisms     

Wenyue HE  Bo SUN  Huijun WANG 《大气科学进展》2021,38(10):1706-1722

Atmospheric water vapor content(WVC) is a critical factor for East Asian winter precipitation. This study investigates the dominant modes of interannual variability in WVC over East Asia during winter and their underlying mechanisms.Based on the empirical orthogonal function(EOF) method, the leading mode(EOF1, R~2 = 28.9%) of the interannual variability in the East Asian winter WVC exhibits a meridional dipole pattern characterized by opposite WVC anomalies over northeastern China and eastern China; the second mode(EOF2, R~2 = 24.3%) of the interannual variability in the East Asian winter WVC exhibits a monopole pattern characterized by consistent WVC anomalies over eastern China. EOF1 is mainly modulated by two anomalous zonal water vapor transport(WVT) branches over northeastern China and eastern China, which are associated with an anomalous atmospheric wave train over Eurasia affected by sea ice cover in the Kara Sea-Barents Sea(SIC-KSBS) area in the preceding October-November(ON). EOF2 is mainly modulated by an anomalous westerly WVT branch over eastern China, which is associated with a circumglobal atmospheric zonal wave train in the Northern Hemisphere. This circumglobal zonal wave train is modulated by concurrent central and eastern tropical Pacific sea surface temperature anomalies. The SIC-KSBS anomalies in ON and the concurrent SST anomalies over tropical Pacific may partially account for the interannual variability of EOF1 and EOF2 winter WVC, and thus may provide a theoretical basis for improving the prediction of winter climate over East Asia.  相似文献   

The political ecology playbook for ecosystem restoration: Principles for effective,equitable, and transformative landscapes     

《Global Environmental Change》2021

The urgency of restoring ecosystems to improve human wellbeing and mitigate climate and biodiversity crises is attracting global attention. The UN Decade on Ecosystem Restoration (2021–2030) is a global call to action to support the restoration of degraded ecosystems. And yet, many forest restoration efforts, for instance, have failed to meet restoration goals; indeed, they worsened social precarities and ecological conditions. By merely focusing on symptoms of forest loss and degradation, these interventions have neglected the underlying issues of equity and justice driving forest decline. To address these root causes, thus creating socially just and sustainable solutions, we develop the Political Ecology Playbook for Ecosystem Restoration. We outline a set of ten principles for achieving long-lasting, resilient, and equitable ecosystem restoration. These principles are guided by political ecology, a framework that addresses environmental concerns from a broadly political economic perspective, attending to power, politics, and equity within specific geographic and historical contexts. Drawing on the chain of explanation, this multi-scale, cross-landscapes Playbook aims to produce healthy relationships between people and nature that are ecologically, socially, and economically just – and thus sustainable and resilient – while recognizing the political nature of such relationships. We argue that the Political Ecology Playbook should guide ecosystem restoration worldwide.  相似文献