不同结构型式及高程离岸潜堤投射系数实验研究     

李玉龙  庞亮  孙国峰 《中国海洋大学学报(自然科学版)》2014,44(1)

针对威海九龙湾岸滩治理工程,进行不同结构型式及不同高程离岸潜堤的物理模型试验。根据物理模型试验的结果,得出离岸潜堤透射系数Kt与主要影响因子的相互关系。得出影响潜堤透射系数最主要的因子为相对堤顶水深(a/Hi),在一定水位条件下,相对堤顶长度(B/L)也能影响透射系数。借助MATLAB数学软件平台,将数据进行回归分析,得出不规则波作用下潜堤透射系数的经验公式,为此类工程设计提供参考。  相似文献   

轻质硬壳堤坝在沿海滩涂中的应用     

陶松垒  陶钧甫  李未材  杨洁  叶良 《海岸工程》2004,23(1):29-34

为了能在各种不同地质的滩涂中发展水产养殖,快速、经济、高效地建造堤坝,提出了硬壳轻质堤坝在滩涂水产养殖中的应用结构体系。阐述了硬壳轻质堤坝的构造和材料、施工工艺及设计方法。具有施工快、稳定性好、防冲蚀、防渗性好的特点,从而提高软弱地基和砂土地基滩涂上的养殖效益。  相似文献   

防潮堤坝对山东昌邑滨海湿地植物及土壤性质的影响分析   总被引：2，自引：2，他引：0  

陈琤  刘玉虹  陆滢  王光美  张华 《海洋科学》2017,41(5):50-58

为研究防潮堤坝对滨海湿地植物及土壤性质的影响,本研究在昌邑国家级海洋生态特别保护区内,通过样线法进行野外调查采样,进行防潮堤坝内外土壤、植被以及两者之间联系的分析,研究了堤坝内外植被及土壤性质差异。结果表明:堤坝内外土壤、植被有一定的差异;堤坝外部土壤C、N、P含量小于堤坝内部,堤坝外部土壤盐度大于堤坝内部;堤坝外部是以盐地碱蓬(Suaeda salsa)和獐毛(Aeluropus sinensis)为主滨海湿地景观,堤坝内部则是以柽柳(Tamarix chinensis)为主的灌草丛景观;保护区内物种丰富度与土壤盐度值呈负相关关系,随着盐度的升高,堤坝外部物种丰富度低于堤坝内部;芦苇(Phragmites australis)体内TC、TN、TP及C︰N︰P与土壤C、N、P含量及C︰N︰P没有明显相关性,而柽柳体内N含量与土壤P含量呈明显负相关关系,说明木本植物比草本植物更加依赖土壤中营养元素的供给。  相似文献   

五大连池地区火山岩年代学研究   总被引：2，自引：0，他引：2  

李齐  陈文寄  李大明  计凤桔  任锦章  杨森林 《地质论评》1999,45(7):393-399

本文对五大连池地区火山的喷发时代、活动时序进行了较为详细的研究。通过对样品中细晶橄榄石含过剩氩这一问题,对已有的年龄数据的可用性进行了分析对比,得到了五大连池地区火山岩中橄榄石含量对年龄数据的影响程度,即当样品中细晶橄榄石含量在5％左右时,对200 ka左右的年龄结果,其影响程度在5％以下。根据已有的同位素测年结果,将五大连池火山群的喷发时间分为1.3 Ma、0.9~0.8 Ma、0.6~0.45 Ma、0.38~0.24 Ma、0.16 Ma、0.09 Ma和270 a 7个时段;根据喷发时段,可以得出五大连池火山群活动自中更新世以来其喷发间隔大约为70~80 ka。  相似文献   

两种治理洞庭湖的实用技术     

龙昭陵 《湖南地质》1999,18(4):271-274

精确地测量湖垸高差,是“退田还湖、移民建镇”的科学依据,堤身隐患探测及坝基稳定性评价,是加固干堤的基本前提。ＧＩＳ及高密度电阻率法两种先进实用技术,是项目实施的先进手段。  相似文献   

Formation Age of the Sujiagou Komatiites in Western Shandong: Further Constraints from SHRIMP U‐Pb Zircon Dating on Granitic Dykes     

WAN Yusheng  DONG Chunyan  XIE Hangqiang  WANG Shijin 《《地质学报》英文版》2020,94(4):877-883

Komatiites are presented as direct evidence for higher mantle temperatures during the Archean. In the North China Craton, komatiites with spinifex structure have been identified only at one locality, i.e. the Sujiagou area, western Shandong. They were considered as formed during the early Neoarchean mainly based on their association with supracrustal rocks considered to be that age. This study carried out SHRIMP U-Pb zircon dating on metamorphosed trondhjemitic and monzogranitic dykes intruding the Sujiagou komatiites, and they have magmatic zircon ages of 2592 ± 12 Ma and 2586 ± 13 Ma respectively. This provides direct evidence that the komatiites formed during the early Neoarchean.  相似文献   

Post‐tectonic clastic dykes in the Dalradian of Scotland and Ireland: implications for delayed lithification and deformation of sediments     

C. A. Phillips  G. I. Alsop 《Geological Journal》2000,35(2):99-110

Structures associated with soft‐sediment deformation are preserved in the Neoproterozoic Dalradian Supergroup of SW Scotland and NW Ireland. Clastic dykes display a range of age relationships to regional Caledonian D₁ folds and fabrics from pre‐tectonic to hitherto unrecognized post‐tectonic. Evidence for the post‐D₁ timing of some dykes includes the emplacement of centimetre‐scale injections along regional S₁ cleavage, the disorientation and transport of cleaved wall‐rock clasts within larger dykes, and clastic dykes which markedly cross‐cut and transect F₁ fold hinges and axial planes. Collectively, these observations are compatible with the earliest regional (D₁) structures deforming a sequence which contained locally overpressured and unlithified pockets of sediment. These critical relationships indicate that overpressured pockets of unlithified sediment were possibly retained within the Dalradian for significant periods of time spanning at least 120 Ma given existing isotopic constraints. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

Geochronology,Geochemistry, and Implications of Aplite Dyke in the Giant Jiama Porphyry Copper System,Tibet          下载免费PDF全文

QI Jing  TANG Juxing  LIN Bin  YANG Hairui  TANG Xiaoqian  TANG Pan  FANG Xiang  ZHANG Tingting  LI Faqiao  SUN Miao  WANG Mengdie  CUI Hao  XIE Jinling 《《地质学报》英文版》2023,97(5):1406-1421

Jiama is a giant, high-grade porphyry copper system in the Gangdese metallogenic belt, Tibet. Multistage intermediate–felsic porphyries intruded in this deposit, some of which are strongly associated with copper-polymetallic mineralization. These ore-bearing porphyries include monzogranite, granodiorite, and quartz diorite porphyries. A new granite aplite dyke was found in the south of Jiama. Its age, genesis, and relationship with ore-related magmatism are obscure. Here, its emplacement age and...  相似文献