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41.
东太平洋多金属结核分布的二维趋势面分析   总被引:1,自引:0,他引:1  
对规则网的 469个测站的多金属结核丰度和 93个测站的 Mn、 Cu、 Co、 Ni元素进行趋势面分析 ,经 F检验 ,各变量的变异性显著 ,拟合度较低 ,表明多金属结核丰度及 Mn、Cu、Co、Ni金属元素的控制因素比较复杂。趋势面分析结果与相关分析结果一致 ,Mn、Cu、Ni元素有极相似的趋势特征 ,有两个轴向分布 ,一个为东西向轴 ,高值区在东部 ,另一个为北西向轴 ,高值区在北西部 ;结核丰度与 Co也有极相似的趋势特征 ,高值区在西部。应用逐次趋势面分析的结果将结核丰度的地质特征分解成各种简单控制因素的叠加 ,使对多金属结核的控矿因素、分布规律和物质来源的研究方法多样化  相似文献   
42.
动态基准实时测量系统的开发与应用   总被引:3,自引:0,他引:3  
介绍了动态基准实时测量系统的硬件组成、站点上全站仪棱镜组合安装与检测方法、系统软件的开发及特点,最后对系统在广州地铁某地铁站结构变形自动监测中的应用情况进行了阐述。通过实际应用表明该系统能应用在自动化、高精度的变形监测领域。  相似文献   
43.
LU  Yongjun 《中国海洋工程》2002,16(1):107-122
A 2-D mathematical model of tidal current and sediment has been developed for the Oujiang Estuary and the WenzhouBay. This model accomodates complicated features including multiple islands, existence of turbidity, and significant differ-ence in size distribution of bed material. The governing equations for non-uniform suspended load and bed load transport arepresented in a boundary-fitted orthogonal curvilinear coordinate system. The numerical solution procedures along with theirinitial conditions, boundary conditions, and movable boundary technique are presented. Strategies for computation of thecritical condition of deposition or erosion, sediment transport capacity, non-uniform bed load discharge, etc. are suggested.The model verification computation shows that, the tidal levels computed from the model are in good agreement with the fielddata at the 18 tidal gauge stations. The computed velocities and flow directions also agree well with the values measuredalong the totally 52 synchronously observed verticals distributed over 8 cross sections. The computed tidal water throughputsthrough the Huangda‘ao cross section are close to the measured data. And the computed values of bed deformation fromYangfushan to the estuary outfall and in the outer-sea area are in good agreement with the data observed from 1986 to 1992.The changes of tidal volumes through the estuary, velocities in different channels and the bed form due to the influence of thereclamation project on the Wenzhou shoal are predicted by means of this model.  相似文献   
44.
45.
Abstract

With the large-scale development and utilization of ocean resources and space, it is inevitable to encounter existing submarine facilities in pile driving areas, which necessitates a safety assessment. In this article, by referring to a wharf renovation project as a reference, the surrounding soil response and buried pipe deformation during pile driving in a near-shore submarine environment are investigated by three-dimensional (3D) numerical models that consider the pore water effect. Numerical studies are carried out in two different series: one is a case of a single pile focusing on the effect of the minimum plane distance of the pile–pipe, and the other is a case of double piles focusing on the effect of the pile spacing.  相似文献   
46.
Since the beginning of formation of Proto-Taiwan, the subducting Philippine (PH) Sea plate has moved continuously through time in the N307° direction with respect to Eurasia (EU), tearing the EU plate. The subducting EU plate includes a continental part in the north and an oceanic part in the south. The boundary B between these two domains corresponds to the eastern prolongation of the northeastern South China Sea ocean-continent transition zone. In the Huatung Basin (east of Taiwan), the Taitung Canyon is N065° oriented and is close and parallel to B. Seismic profiles show that the southern flank of the canyon corresponds to a fault with a normal component of a few tens of meters in the sediments and possible dextral shearing. Several crustal earthquakes of magnitude >%6 are located beneath the trend of the Taitung Canyon and focal mechanisms suggest that the motion is right-lateral. Thus, faulting within the sedimentary sequence beneath the Taitung Canyon is a consequence of underlying dextral strike-slip crustal motions. As the continental part of the EU slab located north of B has been recently detached, some subsequent dextral strike-slip motion might be expected within the EU slab, along the ocean-continent transition zone, which is a potential zone of weakness. We suggest that the dextral strike-slip motion along the ocean-continent boundary of the EU slab might trigger the observed dextral strike-slip motion within the overlying PH Sea crust and the associated faulting within the sediments of the Huatung Basin, beneath the Taitung Canyon. An erratum to this article is available at .  相似文献   
47.
土工布充砂袋的应用及其研究进展   总被引:10,自引:1,他引:10  
张文斌  谭家华 《海洋工程》2004,22(2):98-104
对土工布充砂袋技术和国内外的应用进行了介绍。鉴于土工布充砂袋属于一种新兴起的土工新材料和新技术,在设计和工程实际中还存在着许多急待解决的问题,着重对各种典型状态和典型环境下的土工布充砂袋的变形、应力和土工布充砂袋堆的稳定性研究进展进行综述,最后提出进一步研究的思路。  相似文献   
48.
分析了软土、湿地、滩涂地区特殊地理环境对测量控制点的影响;主要探讨了此类地区控制点标志的设计、施工。借助于建筑桩基技术和道桥施工方法,首次成功实现了某三角洲湿地滩涂地区统一布网。几年来,结合滩涂湿地测量、海岸防护和滩涂开发工程对部分控制点进行了初步检测,给出了部分检测数据。应用和检测均表明:桩基标石可较好地解决软土、湿地、滩涂地区控制点布设难题,显著提高软土海岸地区测量控制点标志的稳固性,从而延长控制网的可使用期。  相似文献   
49.
哀牢山-红河断裂带中段应变分析   总被引:1,自引:0,他引:1  
对哀牢山—红河断裂带中段和平—水塘剖面、墨江—元江剖面和其它地段的岩石应变及磁组构进行了分析,表明应变强度的校正磁各向异性度PJ从断裂带向西至三叠系明显降低,变形强度向西迅速减弱。磁化率椭球体主轴展布反映出剪切带内、外变形方式的改变。剪切带内,以水平走滑运动为主;向西则以水平缩短为主。在应变分析中,对断裂带内的S—C组构两组面理夹角、杏仁体和石榴石应变标志体进行了测量,结果显示,剪切带内的磁组构和岩石组构间关系较差。此外,还对这两条剖面中的三叠系进行了应变和磁组构分析,找出了它们与磁化率椭球体对应轴率间的相关性。  相似文献   
50.
An analysis of statistical expected values for transformations is performed in this study to quantify the effect of heterogeneity on spatial geological modeling and evaluations. Algebraic transformations are frequently applied to data from logging to allow for the modeling of geological properties. Transformations may be powers, products, and exponential operations which are commonly used in well-known relations (e.g., porosity-permeability transforms). The results of this study show that correct computations must account for residual transformation terms which arise due to lack of independence among heterogeneous geological properties. In the case of an exponential porosity-permeability transform, the values may be positive. This proves that a simple exponential model back-transformed from linear regression underestimates permeability. In the case of transformations involving two or more properties, residual terms may represent the contribution of heterogeneous components which occur when properties vary together, regardless of a pair-wise linear independence. A consequence of power- and product-transform models is that regression equationswithin those transformations need corrections via residual cumulants. A generalization of this result isthat transformations of multivariate spatial attributes require multiple-point random variable relations. This analysis provides practical solutions leading to a methodology for nonlinear modeling using correct back transformations in geology.  相似文献   
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