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1.
通过对2 131km高分辨率浅地层剖面资料分析和研究,揭示了威海市近海海域浅地层结构特征,分析了海洋灾害地质因素类型及分布特征,并绘制了主要灾害地质因素分布图。威海市近海海域65m以浅地层共分为5层,第一层为全新世泥质楔形体,地层厚度8~15m;第二层为末次盛冰期以来的海侵层,厚度一般小于3m;第三层为MIS2期的陆相沉积层,地层厚度3~8m;第四层为MIS3期的海相沉积层,厚度3~6m;第五层未完全揭示。近海海域灾害地质因素主要包括埋藏下切谷、浅部断层、浅层气、海底沙波沙脊、浅埋起伏基岩等5种类型;埋藏下切谷主要分布在南部海域U3地层单元中;浅部断层主要分布在南部海域水深大于20m的海底堆积平原;浅层气主要分布在北部海域,东部和南部海域面积较小;海底沙波沙脊主要分布在荣成成山头外海海域;浅埋起伏基岩主要分布在基岩海岸和岛屿较近的海域。  相似文献   

2.
该文在东营市海洋地质调查获得大量数据的基础上,开展近海海域地质环境质量综合评价,反映近海海域地质环境质量现状和变化趋势,为海洋经济的可持续发展和海洋生态环境保护提供依据。选取海岸侵蚀与淤积、活动断裂与地震、灾害地貌与滑坡、浅层气、底辟、埋藏古河道(古湖泊)、表层沉积物质量、海水质量、软土、砂土液化10项指标,采用层次分析法和综合指数法,对东营市近海海域地质环境质量进行了评价。结果表明:研究区大部分区域地质环境质量为优等和良好级别,面积8875km~2,占总面积的86.58%;中等区主要分布在研究区的北部、东南部和东营港近岸区,面积1200km~2,占总面积的11.71%;较差区主要分布在研究区的北部及黄河口外围海域,面积175km~2,占总面积的1.71%。  相似文献   

3.
日照近岸海域灾害地质类型主要为埋藏下切谷、海底侵蚀、冲刷沟槽和冲刷陡坎及海底抛泥区等。通过对日照海岸带近岸海域的浅地层剖面和水深测量资料,开展主要地震地层界面的追踪和对比,结合沉积物粒度和地球化学特征,对近海海域潜在灾害地质因素进行分析对比,探讨了日照近海海区的灾害地质类型、特征和分布规律,为半岛蓝色经济区的海洋开发提供基础地质资料。  相似文献   

4.
根据收集到的日照市海岸带浅地层剖面测量调查资料,把多条浅地层剖面中出露的古河道断面推测性地连接起来,重建了以往的古河道体系,综合分析了日照市海岸带古河道的分布特征。日照近海区域存在一个主干河道呈SW-NE走向的梳状河道网,古河道形成于距今约4.4万a的末次冰期。古河道的形成是河流的侵蚀、搬运、沉积及后期的海平面上升、潮汐改造等多种因素共同作用的结果。在末次冰期,研究区内气候湿润,河流流速较大,河流搬运泥沙的能力较强,长期侵蚀作用形成下切古河道,在古河道中容易形成淤积较多河流携带的砂体。古河道断面形态主要呈U形、V形、W形、箱形和倒梯形。主干河道北西侧,分支河道较密,南东侧分支河道较稀疏。主河道长约40km,横截面由南西向北东逐渐变宽,最宽处达4km。分支河道多数以NW向为主,少数为NE向,长度介于8~20km之间,宽度约为1~3km。古河道主要位于16~24m水深的闭合深度以外区域,对其中的砂体经过粒度筛选可作为将来进行人工抛沙的砂源。  相似文献   

5.
黄河三角洲是陆海交界地带,陆地海洋相互作用显著,泥沙所引起的岸滩演变、港口航道的淤积、水动力环境的改变等问题比较复杂。该文采用三维HEM-3D数值模型对黄河三角洲海域流场变化、盐度、悬浮泥沙浓度及海岸冲淤分布进行了潮流周期内的数值模拟分析。结果表明,黄河三角洲海域的悬浮泥沙浓度分布与潮流场变化和河口泥沙输入有密切的关系,在三角洲北部受五号桩外强潮流区的影响,近岸海底的泥沙发生明显的再悬浮,并在涨潮流向南输送,含沙量达1.5 g/L左右。在三角洲南部(现行河口区域和莱州湾区域),受现行河口入海泥沙扩散的影响显著。海域年冲淤分布,在北部废弃三角洲区域,由于海洋动力作用强烈,浅水冲刷,海底侵蚀显著,形成了明显呈沿岸展布的侵蚀中心,在侵蚀中心以外,侵蚀快速减弱。在现行河口区域,以淤积为主,在羽状流扩散的控制下,泥沙入海后向南输运,至莱州湾区域逐渐减弱。数值模拟的结果与卫星遥感解译的岸线变化基本一致,效果良好。  相似文献   

6.
海洋牧场是改变近海生态环境和增养殖水产资源的渔业模式,其聚鱼效应、改善海域生态环境及增殖渔业资源效果明显。该文选用海水深度及质量、海底地形、地层结构、沉积物类型、水动力条件等指标对日照市海洋牧场示范区人工鱼礁选址适宜性进行评价,评价结果显示:日照市4个国家级海洋牧场示范区和8个省级海洋牧场示范区中,不适宜建设人工鱼礁的海洋牧场有5个,适宜的有7个,主要位于日照市北部的两城镇东南侧海域和南部的涛雒镇东侧海域。7个海洋牧场所在海域离岸3~20km,水深6~22m,沉积物以砂为主,海底地势平缓,海底表面承载力为5~6t/m~2,流速介于0.2~0.8m/s,海水水质清洁,饵料生物丰富。  相似文献   

7.
该文在威海市海岸带综合地质调查项目的基础上,根据陆域和海域不同的地质环境条件,分别进行了地质环境承载力综合评价。陆域选取了3个一级评价因子和13个二级评价因子建立地质环境承载力评价指标体系,利用层次分析法取得各评价因子权重,再利用模糊数学综合指数法进行了综合评价。海域选取了海底沉积物重金属污染、海底沙坡沙脊、浅层气、浅埋基岩和埋藏下切谷等5个评价因子,采用叠加法进行了综合评价。最终,将研究区地质环境承载力划分为强区、较强区、一般区、较弱区等4类。研究区陆域地质环境承载力相对较强,占总面积的67.67%;其次为一般区,占总面积的31.67%;较弱区零星分布,仅占总面积的0.66%。近海地质环境承载力总体较强,一般区主要分布在威海湾西部,较弱区分布在威海湾以北的广阔海域。  相似文献   

8.
黄河三角洲埕岛地区近年海底冲淤规律及水深预测   总被引:10,自引:1,他引:9  
通过对1976~1995年黄河三角洲地区埕岛海域的水深资料以及近年来实测的水深数据的分析,确定了黄河三角洲埕岛地区在1976年黄河改道清水沟后,从三角洲推进淤积期进入了海岸冲刷改造期。按冲刷速率、剖面坡度及其与季节变化的关系可分为快速冲刷阶段(1976~1980)、缓慢冲刷阶段(1981~1992)、以冲刷为主的冲淤调整阶段(1992年至今),海岸边带的后期冲刷改造受季节性影响也比较明显。在深度上基本以15m等深线为界,深水区淤积、浅水区冲刷。通过250m×250m网格化节点的实测水深变化的时间序列,采用二维平面的趋势面拟合方法,可以较好地对本海区的水深进行拟合并做出时间序列值的预测。  相似文献   

9.
通过对滨州近海海域海底沉积物测试数据及海岸带陆域土壤地球化学分析,对滨州海岸带陆域土壤和海底沉积物中7种重金属(Hg,Cd,Pb,Cu,Zn,Cr,Ni)的空间分布特征进行了研究,并绘制了各指标含量陆海联合分区图。分析结果表明,滨州市海岸带重金属元素含量基本上均低于国标规定的海洋一类沉积物的最高标准,仅有个别元素含量超过一级标准值,表明局部存在一定的重金属污染。从滨州海岸带重金属含量空间分布上来看,除Hg元素外,其余重金属元素含量呈现一定的规律,基本上陆域含量高于海域含量,且大部分元素都呈现出陆域城镇值高,郊区值低的态势。区内化工企业较发达,Ni,Cr属于中度变异区,Cd,Hg,Pb属于高度变异,受人为影响因素较大,考虑区内土壤及海底沉积物重金属富集主要来源于工业"三废"。  相似文献   

10.
利用InSAR技术获取2008-03-21新疆于田MS7.3地震的同震和震后形变场。同震分布式滑动反演结果表明,同震断层最大滑动量达5.4 m,主要分布在南部断层的0~5 km深度附近,地震以正断错动为主,兼有左旋走滑分量。震后形变结果表明,发震断层北段两侧存在差异性运动,最大累积差异形变在震后782 d达15 cm。进一步分析表明,震后断层余滑可能是震后形变的主要机制。余滑反演结果表明,震后2 a断层余滑量相对较小,滑移区范围明显减小且均位于浅部区域,北部断层能量释放较彻底,南部仍存有少量能量,整体能量基本释放完。  相似文献   

11.
12.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

13.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose  相似文献   

14.
<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail  相似文献   

15.
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo-  相似文献   

16.
<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a  相似文献   

17.
As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m.  相似文献   

18.
Foreword     
正Rapid changes of Arctic sea ice cover have been in the focus of the international climate research community in recent years.Quite a few of nations have completed a large number of related surveys and research projects in the Arctic Ocean.Up to now,China has performed six research cruises to the Arctic Ocean resulting in a significant volume of research output.Improved knowledge on the atmospheree-sea ice-ocean interactions in the Arctic is a  相似文献   

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20.
The GRV 024516 and GRV 024517 meteorite samples collected from Grove Montains,Antactica are ureilite and H5 ordinary chondrite,respectively.Based on the study of mineralogy-petrology,the cosmic-ray exposure ages and gas retention ages of these two meteorites were determinated and calculated.Their cosmic-ray exposure ages are 33.3 Ma,51.7 Ma,and gas retention ages are 1936.8 Ma and 3720 Ma,respectively.The ureilite contains diamond,graphite and amorphous C,which are mainly carrier of noble gases indicating obviously shock metamorphism effects,which induced 40Ar partial loss.The H5 chondrite indicates thermal metamorphism of parent body,its gas retention age fall the range between 3220 Ma and 4510 Ma of the least shocked H5 chondrites  相似文献   

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