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961.
962.
WEB平台下地理信息系统的构造方法和模型 总被引:2,自引:0,他引:2
WEB平台下地理信息系统的主要构造方法有CGI法,服务器应用程序接口,插件,ActiveX控件,Java Applet法等。构造模型有B/S三层结构,基于中间件的B/S多层结构,交互操作,空间数据源的分步骤服务模型等。传统的GIS系统固有的封闭性决定了不同的GIS平台下的空间数据无法共享,选择成熟的构造方法和构造模型,建立WEB平台下的地理信息系统,通过WEB浏览器访问GIS空间数据库,实现真正的空间数据共享。 相似文献
963.
本文概述了国产高压电器设备在埕岛海上油田采油平台的应用情况。并着重对电器元器件的研制,装配,工艺,三防等问题进行了有益的探讨。 相似文献
964.
SONG Yupu FENG Sheng KANG Haigui
Professor Ph. D. PhD Supervisor State Key Laboratory of Coastal Offshore Engineering Dalian University of Technology 《中国海洋工程》1999,(3)
This paper proposes an optimum design medel for the offshore jacket platform considering multi-design criteria,multi-design constraints and the structure-pile-soil interaction,and gives an optimum designprocedure in which the proposed optimum design model is used together with structural analysis softwareSAP91 and optimum algorithm software OPBI.The Chengbei ~#11 offshore platform,which lies in theShengli oil field,is designed by use of the above optimum design model.The results show that the optimumdesign model is stable,and it depends on neither the optimization algorithm nor initial values of design vari-ables.All values of the objective function converge to the same minimum value,and the speed of conver-gence is high,showing that the proposed optimum design model is reasonable. 相似文献
965.
—By means of nonlinear pushover collapse analysis approach,the aseismic reliability analysesof two offshore jacket platforms in the Bohai Gulf in China are studied according to their ocean locationand environmental loadings there.On the basis of those analyses,an aseismic reliability analysis approachis presented.The results show that the aseismic reliability of those platforms is high.Also it is proved thatthis aseismic reliability analysis approach is simple,practical and reliable. 相似文献
966.
967.
To improve the understanding of the distribution of reservoir properties along carbonate platform margins, the connection between facies, sequence stratigraphy, and early diagenesis of discontinuities along the Bathonian prograding oolitic wedge of the northeastern Aquitaine platform was investigated. Eight facies are distributed along a 50 km-outcropping transect in (1) toe-of-slope, (2) infralittoral prograding oolitic wedge, (3) platform margin (shoal), (4) open marine platform interior, (5) foreshore, and (6) terrestrial settings. The transition from shallow platform to toe-of-slope facies is marked in the field by clinoforms hundred of meters long. Carbonate production was confined to the shallow platform but carbonates were exported basinward toward the breakpoint where they cascaded down a 20–25° slope. Ooid to intraclast grainstones to rudstones pass into alternating marl-limestone deposits at an estimated paleodepth of 40–75 m. Three sea-level falls of about 10 m caused the formation of discontinuities corresponding to sequence boundaries. Along these discontinuities, erosional marine hardgrounds formed in a high-hydrodynamic environment at a water depth of less than 10 m, displaying isopachous fibrous cements and meniscus-type cements. The cements pass landward into meniscus and microstalactitic forms along the same discontinuities, which are characteristic of subaerial exposure. During the deposition of transgressive systems tracts, carbonate accumulation remained located mostly on the shallow platform. Energy level increased and carbonates were exported during the deposition of highstand systems tracts forming the infralittoral prograding oolitic wedge. During the deposition of lowstand systems tracts, carbonate production fell to near zero and intraclast strata, derived from the erosion of hardgrounds on the shallow platform, prograded basinward. Early diagenetic cements are related exclusively to discontinuities that are not found within the prograding wedge because of the continuous high sedimentation rate under lower hydrodynamic conditions. This absence of early cementation within the infralittoral prograding oolitic wedge was conducive to porosity conservation, making such features good targets for carbonate reservoir exploration. This study proposes a novel sequence stratigraphy model for oolitic platform wedges, including facies and early diagenesis features. 相似文献
968.
The Early Miocene was a period of active rifting and carbonate platform development in the Midyan Peninsula, NW Saudi Arabia. However, there is no published literature available dealing with the detailed characterization of the different carbonate platforms in this study area. Therefore, this study aims to present new stratigraphic architectural models that illustrate the formation of different carbonate platforms in the region and the forcing mechanisms that likely drove their formation. This study identified the following features formed during active rifting: a) a Late Aquitanian (N4) fault-block hangingwall dipslope carbonate ramp, b) a Late Burdigalian (N7-N8) isolated normal fault-controlled carbonate platform with associated slope deposits, and c) a Late Burdigalian (N7-N8) attached fault-bounded platform with reef buildups, rimmed shelf developed on a footwall fault-tip within a basin margin structural relay zone that formed coinciding with the second stage of rifting. Variations in cyclicity have been observed within the internal stratigraphic architecture of each platform and also between platforms. High-resolution sequence stratigraphic analysis shows to be parasequences the smallest depositional packages (metre-scale cycles) within the platforms. The hangingwall dipslope carbonate ramp and the attached platform demonstrate aggradational-progradational parasequence stacking patterns. These locations appear to have been more sensitive to eustatic cyclicities, despite the active tectonic setting. The isolated, fault-controlled carbonate platform reveals disorganized stratal geometries in both platform-top and slope facies, suggesting a more complex interplay of rates of tectonic uplift and subsidence, variation in carbonate productivity, and resedimentation of carbonates, such that any sea-level cyclicity is obscure. This study explores the interplay between different forcing mechanisms in the evolution of carbonate platforms in active extensional tectonic regions. Characterization of detailed parasequence-scale internal architecture allows the spatial variation in syn-depositional relative base-level changes to be inferred and is critical for understanding the development of rift basin carbonate platforms. Such concepts may be useful for the prediction of subsurface facies relationships beyond interwell areas in hydrocarbon exploration and reservoir modeling activities. 相似文献
969.
我国南海海域海洋环境条件复杂且海水密度垂直层化现象显著,内孤立波活动频繁,因内孤立波而造成海洋开采平台破坏的案例屡见不鲜。依托水动力计算软件AQWA二次开发功能,采用Kdv方程,借助Fortran语言将深水半潜式平台立柱、浮箱、系泊系统3部分的内孤立波作用力叠加到外力项中,联合求解半潜式平台的6自由度动力响应特性。数值模拟结果表明,在内孤立波作用下,半潜式平台的运动及系泊线张力均受到了显著的影响。在不考虑系泊系统受内孤立波作用时,平台在纵荡和横荡方向上产生较大的漂移运动,最大偏移量较无内孤立波情况下增加了8倍;系泊线最大张力提高了17%,增加了系泊线断裂的风险。在考虑系泊系统受内孤立波作用时,平台的纵荡和横荡运动响应在原响应基础上继续提高15%,但是系泊线张力变化不大。内孤立波不同浪向下的平台纵荡和横荡响应相差也很明显;系泊系统合力在不同方向上的大小决定了平台不同方向上运动的大小。 相似文献
970.