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1.
海洋地质调查是我国建设海洋强国的战略需求, 调查产生的数据具有重要的应用价值。随着计算机技术、数据库技术和网络技术的快速发展, 海洋地质调查数据的数字化管理、应用和共享已成为衡量我国海洋科技水平的重要标志。鉴于传统WebGIS应用交互性差, 扩展再利用性能弱的缺点, 文章以南海海洋地质调查数据库为基础, 采用基于Flex技术的应用开发接口(Flex API) 和ArcGIS Flex Viewer应用系统框架进行开发, 并定制自定义的微件(Widget)在应用框架的基础上进行功能扩充, 开发部署在网络环境下的“南海海洋地质调查数据共享服务平台”, 用户能快速、便捷地获取调查数据。文章实现了南海海洋地质调查基本信息的集中管理、展示与服务, 该平台能够较好地满足地勘科技人员与管理人员对海洋地质工作信息服务的需求。 相似文献
2.
《Marine and Petroleum Geology》1987,4(3):255-257
Chronostratigraphic (time-rock) units (e.g. Cretaceous System, Eocene Series, Aptian Stage), divided into lower, (middle), and upper, are appropriate for attribution of age to rocks, and hence to graphic representations such as well logs, colummar sections, seismic sections, and stratigraphic correlation diagrams.Geochronological (time) units (e.g. Cretaceous Period, Eocene Epoch, Aptian Age), divided into early, (middle), and late, are appropriate for designating the time of occurrence of historical events, such as transgressions, periods of erosion and deposition, and episodes of folding or faulting.The dual system of nomenclature, if followed consistently, aids clarity in thought and expression of complex ideas, particularly in describing geological history. 相似文献
3.
福建东山岛地质灾害特征与成因初探 总被引：5，自引：5，他引：0
海岛是海上陆地国土和人类开发海洋的远涉基地及前进支点。海岛大幅度地快速增长的开发活动与工程建设使脆弱的海岛生态环境正遭受到严重威胁。东山岛是福建第二大岛,近10年随着水产养殖与育苗、风电建设、环岛公路和房地产开发等海岛利用和开发强度的加大,海岛地质灾害及潜在风险陡增。基于现场调查和遥感影像解译,分析东山岛赋存的地质灾害类型及其分布,初步探究了主要地质灾害的诱因,为更有效地保护和可持续性开发东山岛,制定合理长效规划、防灾与减灾对策提供准确依据,并为福建及周边基岩岛的地质灾害调查与防治提供实测数据参考。 相似文献
4.
Tectonics, global changes in sea level and their relationship to stratigraphical sequences at the US Atlantic continental margin 总被引：1，自引：0，他引：1
The principal factors that control the extent of seas through geological time are vertical movements of the lithosphere and global changes in sea level. The relative height of the sea surface determines the facies and the thickness of sediments that can accumulate in a sedimentary basin. Backstripping studies show that the primary factors affecting the subsidence of rifted sedimentary basins are thermal contraction, following heating and thinning of the lithosphere at the time of rifting, and sedimentary loading. Factors such as compaction, palaeobathymetry, erosion and global sea level changes also contribute, but their combined affects are small compared to those of thermal contraction and sedimentary loading. Simple models have been constructed which combine the effects of sedimentary loading and thermal contraction with those of compaction, sub-aerial erosion and global changes in sea level. In the models it was assumed that the lithosphere was heated and thinned by stretching at the time of rifting, sedimentary loading occurs by flexure of a lithosphere that progressively increases its flexural rigidity with age following rifting and, that sediment compaction and bathymetry change across a basin but do not vary significantly with gwological time. Furthermore, different assumptions were made on the magnitude of curves of global sea level changes and the relationship between denudation rate and regional elevation. The models show that tectonics, in the form of thermal contraction of the lithosphere and flexure and slowly varying global changes in sea level, can explain a number of the stratigraphic features of the US Atlantic continental margin. In this Paper some of the implications of these results are examined for studies of (a) sea level changes through geological time; and (b) the maturation history of continental margin basins. 相似文献
5.
Search and rescue (SAR) for both airborne and maritime vehicles has been an area of intense investigation for many years. Current techniques include employment of small distress transmitters which provide signals that have only a limited interception capability. This can considerably increase the search time and reduce its effectiveness. With the increased availability-existing and planned-of both synchronous and nonsynchronous satellites, SAR investigations are being directed toward the application of satellites. The present paper introduces the concept of satellite-based maritime search and rescue system (SAMSARS). This is a proposed pseudonoise (PN) wide-band spread spectrum system that would operate at low power levels and coexist with operational communication satellite systems (voice or data) without mutual interference. The use of existing operational satellite spectrum, instead of a dedicated distress channel or special satellites, is a major feature of SAMSARS. Other important aspects are its capability of providing unique identification and distress information in minutes following activation of the distress transmitter and its inherent immunity to false alarms. SAMSARS can also provide position location directly when three satellites are mutually visible or indirectly, by taking advantage of a vessel's on-board derived navigation data. This paper presents concept elements such as message structure, transmitter and receiver block diagrams, and unique features of SAMSARS. The paper also presents an operational example, including sample link power budgets, and finally specifies areas for further investigation. 相似文献
6.
从地质条件、地质环境及地质资源等多角度出发,建立包括地形地貌工程地质、水文地质、不良地质作用和地质灾害、活动断裂和地震效应、岸线资源等6个评价要素,15个评价因子,4个因子划分等级的多层次海岛工程建设地质适宜性评价指标体系,并利用GIS空间分析技术对宁波梅山岛进行评价。在此基础上,叠加梅山岛生态红线管控区,将二级管控区划分为适宜性差区。评价结果表明：梅山岛工程建设适宜性总体良好,适宜-较适宜工程建设区面积占比达75.5%,可满足近期规划建设用地需求;近深水岸线区均为适宜-较适宜,其中未开发利用长度6.1 km,可有效支撑梅山岛国际港口城市新城区建设。该评价结果可为梅山岛的开发利用及生态保护提供科学依据,同时对完善工程建设地质适宜性评价体系具有一定的理论意义。 相似文献
7.
The location of offshore structures for the purpose of recovering deep water resources has provided the impetus to more accurately predict forces acting on the structure so that costs can be minimized while the structure can safely withstand environmental forces. Accurate prediction of wave kinematics is a vital step in the more accurate prediction of environmental forces. In this study, a laser Doppler anemometer is used to measure the horizontal velocity under the largest wave occurring in an irregular sea generated in a laboratory wave tank. Specifically, JONSWAP and Pierson-Moskowitz wave spectra were generated in the wave tank and the horizontal velocity was measured at locations both above and below the still water level beneath the wave crest. The laboratory measured velocity values tend to lie between those predicted by linear extrapolation and Wheeler stretching. The results are not consistently predicted by either of the stretching methods, and therefore, it is not known which method will give a more accurate prediction before the data are measured. 相似文献
8.
《Marine Policy》2014
The concept of base-multiplier analysis is that export activities constitute the economic base of a region, whereas the other economic activities that sell their goods and services to the local residents grow or shrink depending on the performance of the base activities. These concepts, with origins extending at least as far back as the early 1900s, have reached maturity and are widely applied. The attractiveness of an economic base model (EBM) draws in its simplicity in expressing the power of demand in regional income determination. Extensive literature has grown up around the economic base theory, however, systematic publications concerning empirical application are scarce and focus mostly on the socio-economic dimension of the analyzed system. Such territorially oriented economic models are useful in a variety of decision making procedures; preparation of annual budgets, short-run market demand forecasting, longer-term growth strategies. The purpose of this article is to present a practical application of EBM to the geographical area of the Guadiana Estuary, on the south coast of Portugal. The interest of the EBM application in this case study includes its integration in a broader project that applies a Systems Approach Framework (SAF) towards Integrated Coastal Zone Management (ICZM). There are three pillars of sustainability considered here: social, ecological and economic, hence, the article not only describes EBM application but also how it has been use to demonstrate a chain of events resulting from the interaction between the ecological and the socio-economic sub systems of the area. The results obtained will probably raise the usual criticism to which the economic base model has been exposed previously; however it provides unequivocal evidence that a truly interdisciplinary approach to a given territorial target can be successfully shared with end users and the research community. 相似文献
9.
作为深海科学研究的重要基础装备,深海超长沉积物柱状取样系统在海底地形地貌、海洋地质构造、气候环境变化等研究领域发挥了重要作用,其在海底矿产资源勘探、海洋工程地质勘察等方面展现了巨大应用价值。针对传统超长柱状沉积物取样系统在作业过程中存在的盲目采样、安全隐患大、甲板作业空间受限等问题,自主研制了一套适用于深海的超长可控可视沉积物柱状取样系统,该系统具有液压锤击、立式收放和实时监控功能,能获取连续、超长、具有精准姿态方位信息的柱状沉积物样品。现通过对独立排缆方式、取样管快速拆装、样品封堵、低扰动取样刀头等关键技术细节进行优化,解决了样品扰动大、取样率低的问题,提高了取样作业效率与样品质量,且降低了作业安全风险。2017—2021年,该取样系统搭载不同母船在南海1 700,1 725 和1 778 m水深分别获取了15.25、16.01和15.83 m的长柱状沉积物样品。该设备的成熟应用,可为我国深海探测研究提供技术支持。 相似文献
10.
富钴结壳资源远景区圈定方法 总被引：2，自引：0，他引：2
提出了4种不同的富钴结壳资源远景区圈定方法,即水深法、工程间距外推法、网格微分法和综合法,对比了它们的优缺点,对同一研究区运用不同的方法圈定了不同的资源远景区并进行了资源评价,结果表明:这几种方法是层层递进、相辅相成的,水深法和工程间距外推法可以给出研究区资源远景的大致范围,网格微分法是圈定较为精确资源远景区的基础,但是,加入地质规律的综合法可以提供更接近真实情况的资源远景区。不同的方法适合不同的勘探程度和不同研究目的,并且有不同的精度。 相似文献
11.
远程遥控水下机器人系统是一种先进的海洋综合调查设备,能够实现海底长时间、高精度的定点取样作业及其他精细调查,在海洋区域地质调查中利用ROV开展高精度海底取样及其环境调查方面具有其他调查设备无法比拟的优越性。ROV具有功能多、综合作业能力强、安全可靠和实时遥控等优点。目前国内利用ROV进行海洋区域地质调查还处于起步阶段,随着ROV在海洋调查中的应用技术不断成熟和完善,利用ROV进行海洋区域地质调查将大大提高海洋区域地质调查的装备水平和调查精度,具有广阔的应用前景。以＂海狮号＂ROV系统为例,介绍其在我国海洋区域地质调查中的典型应用。 相似文献
12.
Abstract. Living, symbiont-bearing, larger foraminiferids restricted to the photic zone incorporate mechanisms blocking solar radiation and water current transportation. They can be divided in two groups according to their wall structure: 1, Families with opaque test walls, reducing light penetration: Peneroplids inhabit shallow-water environments from the intertidal ( Peneroplis in large numbers) down to 40 m ( Dendritina , preferring sandy substrates). Soritids are restricted to subtidal environments with less water turbulence and range from the reef moat down to 60 m. Amphisorus and Marginopora are common down to 30 m, whereas Parasorites is restricted to deeper parts of the reef slope. Alveolinella can be found in the upper 40 m of the reef slope. 2. Families with hyaline test walls, adjusted for light penetration: amphisteginids inhabit the whole photic zone, demonstrating a correlation of test flattening with increasing depth. Calcarinids cling with their spines to firm substrates such as algal thalli or macroids. Baculogypsina is restricted to high energetic regions on the reef flat. Calcarina inhabits similar environments, extending its distribution range within fore reefs down to 80 m. Baculogypsinoides is a dominant calcarinid genus from 30 to 70 m depth. Within nummulitids, Heterostegina prefers hard substrates on the reef slope, while Assilina (= Operculina ) is frequent in deeper parts and is independent of substrates. Sandy bottoms from 30 to 60 m are inhabited by the last living representative of the genus Nummulites, N. venosus . The giant foraminifer Cycloclypeus , with test sizes up to 7 cm, is restricted to fore reef areas below 50 m down to the base of the photic zone. 相似文献
13.
B. Gjevik D. Hareide B. K. Lynge A. Ommundsen J. H. Skailand H. B. Urheim 《Marine Geodesy》2006,29(1):1-17
A system for displaying tidal currents in an electronic chart display and information system (ECDIS) has been developed and implemented in compliance with the standards of the International Hydrographic Organization (IHO). The tidal current fields can be displayed in real time on the electronic navigational chart and several options and functions for updating and zooming have been designed. The current fields are calculated from a data base with the harmonic constants for the four major tidal constituents. The harmonic constants are obtained from a high resolution numerical model with horizontal grid resolution of 100 m. The model is validated by comparing with sea level and current measurements. The depth matrix for the central part of the model domain was calculated from data from multibeam bathymetric surveys. An application example of the implementation is given for Trondheimsleia, a part of the main sailing route along the western coast of Norway. 相似文献
14.
深海岩芯取样钻机是开展海洋科学研究、深海资源探测和海底地质取样所必备的关键性装备,随着深海运载器的大规模应用,利用运载器优势发展深海运载器小型岩芯取样探测技术得到了国内外学者的关注,并形成了研究热点方向。在深海运载器作业工具应用认识基础上,首次聚焦运载器岩芯取样钻机研究,对国内外运载器岩芯取样钻机的发展现状、技术特点进行了全面综述。同时,基于"蛟龙"号岩芯钻机研制及应用经验,讨论了发展运载器岩芯取样钻机的关键技术。最后总结了后续发展方向,以期为我国深海运载器岩芯钻机的研发和应用提供技术参考。 相似文献
15.
16.
Forced regressive wedge in the Mesoproterozoic Koldaha Shale,Vindhyan basin,Son valley,central India
The present paper highlights the sequence development within the Mesoproterozoic Koldaha Shale Member of the Kheinjua Formation, Vindhyan Supergroup which records the occurrence of a forced regressive wedge and associated discontinuity surfaces at the base of the wedge. Nine lithofacies have been identified within the study area that are grouped into three lithofacies associations varying in depositional setting from outer shelf, through shoreface-foreshore-beach to continental braidplain. The outer shelf sediments are aggradational to slightly progradational representing highstand systems tract. The rapidly progradational, wedge-shaped shoreface to foreshore-beach succession occurs sharply or erosively above the outer shelf sediments and is bounded by a regressive surface of marine erosion (RSME) at the base and by a subaerial unconformity at the top. This, along with its downstepping trajectory, supports deposition of this sedimentary wedge during falling sea level. A laterally extensive soft sediment deformation zone occurs at the base of the wedge.The forced regressive wedge is incised by fluvial braidplain deposits that rest on an erosive surface representing a sequence boundary. The thin braidplain deposits are the product of aggradation during a subsequent early rise in relative sea level, and thus, they are inferred to represent a lowstand systems tract. The constituent architectural elements that characterize the braidplain deposits are downstream accretion elements and small channel elements. Further landward, the base and top of the shoreface wedge merge to form an unconformity across deposits that rest directly on the outer shelf sediments. The identification of forced regressive wedges has significant economic importance in view of the potential occurrence of hydrocarbons within the Proterozoic formations. 相似文献
17.
稳定平台是海洋重力仪十分重要的组成部分,在测量中它能够为重力仪提供一个水平基准面,确保重力数据的质量.但在测量中,稳定平台倒台是常见故障,也是十分严重的故障,如不能及时维修,将会导致测量工作的中断.研究稳定平台倒台故障的原因及维修技巧,可为技术人员更好地掌握设备,有效排除仪器故障提供很好的帮助.稳定平台倒台故障的原因很... 相似文献
18.
《Coastal Engineering》1999,36(2):147-163
Observations of waves as a time series from a fixed or moored sensor are shown to underestimate the extreme waves occurring in the vicinity. The underestimate arises because of the difference in phase and envelope propagation of surface water waves so that the highest crest, for example, is recorded only when the crest coincides with the envelope maximum at the location of the wave recorder. In addition, the dispersive nature of water waves can lead to the coalescence of groups of waves as longer waves catch up to shorter slower waves, so that the group shape changes markedly as the waves propagate. Moored accelerometer buoys introduce another error that exacerbates the underestimate of the highest crest—the quasi-Lagrangian motion of the buoy leads to flattening of the crests and sharpening of the troughs so that apparent mean water level is raised and thus the height of crests above it is reduced. An analysis approach to correct these underestimates is outlined and tested with observed data against the predictions of extreme values based on narrow-banded random wave theory. 相似文献
19.
Identification of the main hydrocarbon source rocks of the large Puguang gas field (northeastern Sichuan Basin, southwest China) has been the subject of much discussion in recent years. A key aspect has been the lack of a comprehensive understanding of the development of hydrocarbon source rocks of the Upper Permian Longtan Formation, which had been thought to contain mainly coal seams and thick carbonate layers. In this paper, based on geological data from more than ten wells and outcrops and their related mineralogy and geochemistry, we investigated the depositional environment and main factors controlling organic matter enrichment in the Longtan Formation. We propose a model which combines information on the geological environment and biological changes over time. In the model, organic matter from prolific phytoplankton blooms was deposited in quiescent platform interior sags with rising sea-levels. During the Longtan period, the area from Bazhong to Dazhou was a platform interior sag with relatively deep water and a closed environment, which was controlled by multiple factors including syngenetic fault settling, isolation of submarine uplifts and rising sea-levels leading to water column stratification. Although the bottom water was anoxic, the phytoplankton were able to bloom in the well-lit upper euphotic zone thus giving rise to a set of sapropelic black shales and marlstones containing mostly algal organic matter with minor terrestrial contributions. As a consequence, these rocks have a high hydrocarbon generation potentials and can be classified as high-quality source rocks. The area from Bazhong to Dazhou is a center of hydrocarbon generation, being the main source of reservoired paleo-oils and presently discovered as pyrobitumen in the Puguang gas field. The identification of these source rocks is very important to guide future petroleum exploration in the northeastern Sichuan Basin. 相似文献