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Stephen J. Eaton David M. Hodgson Natasha L. M. Barlow Estelle E. J. Mortimer Claire L. Mellett 《第四纪科学杂志》2020,35(6):760-775
Offshore stratigraphic records from the North Sea contain information to reconstruct palaeo-ice-sheet extent and understand sedimentary processes and landscape response to Pleistocene glacial–interglacial cycles. We document three major Middle to Late Pleistocene stratigraphic packages over a 401-km2 area (Norfolk Vanguard/Boreas Offshore Wind Farm), offshore East Anglia, UK, through the integration of 2D seismic, borehole and cone penetration test data. The lowermost unit is predominantly fluviatile [Yarmouth Roads Formation, Marine Isotope Stage (MIS) 19–13], including three northward-draining valleys. The middle unit (Swarte Bank Formation) records the southernmost extent of tunnel valley-fills in this area of the North Sea, providing evidence for subglacial conditions most likely during the Anglian stage (MIS 12) glaciation. The Yarmouth Roads and Swarte Bank deposits are truncated and overlain by low-energy estuarine silts and clays (Brown Bank Formation; MIS 5d–4). Smaller scale features, including dune-scale bedforms, and abrupt changes in cone penetration test parameters, provide evidence for episodic changes in relative sea level within MIS 5. The landscape evolution recorded in deposits of ~MIS 19–5 are strongly related to glacial–interglacial cycles, although a distinctive aspect of this low-relief ice-marginal setting are opposing sediment transport directions under contrasting sedimentary process regimes. 相似文献
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《Geoforum》2015
South Gobi province is at the center of Mongolia’s mining boom, where companies began exporting minerals over dirt-track roads in the early 2000s. This paper examines recent controversies surrounding road dust near the Oyu Tolgoi copper–gold mine, the so-called coal road from Tavan Tolgoi mines, and the Chinese border. At the time of the research, local residents, particularly nomadic herders, were concerned that dust produced from unpaved mining roads was coating the pasture, causing illnesses among livestock, and endangering their livelihoods in the region. The presence of dust rendered mining an uncomfortably intimate experience as state and corporate actors negotiated responsibility for infrastructure development. The paper builds on the concept “technologies of distantiation” to reveal the complex ways that dust from unpaved roads creates distances and disconnections between people, livelihoods, and landscapes, representing an enclosure of the pasture. Methods for the paper include interviews, focus groups, and participant observation conducted in South Gobi province and Ulaanbaatar in 2010, 2011, and 2012 as well as follow-up research carried out in spring 2015. 相似文献
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Jens Göpfert Franz Rottensteiner Christian Heipke 《ISPRS Journal of Photogrammetry and Remote Sensing》2011,66(6):858-871
For historical reasons many national mapping agencies store their topographic data in a dual system consisting of a Digital Landscape Model (DLM) and a Digital Terrain Model (DTM). The DLM contains 2D vector data representing objects on the Earth’s surface, such as roads and rivers, whereas the DTM is a 2.5D representation of the related height information, often acquired by Airborne Laser Scanning (ALS). Today, many applications require reliable 3D topographic data. Therefore, it is advantageous to convert the dual system into a 3D DLM. However, as a result of different methods of acquisition, processing, and modelling, the registration of the two data sets often presents difficulties. Thus, a straightforward integration of the DTM and DLM might lead to inaccurate and semantically incorrect 3D objects.In this paper we propose a new method for the fusion of the two data sets that exploits parametric active contours (also called snakes), focusing on road networks. For that purpose, the roads from a DLM initialise the snakes, defining their topology and their internal energy, whereas ALS features exert external forces to the snake via the image energy. After the optimisation process the shape and position of the snakes should coincide with the ALS features. With respect to the robustness of the method several known modifications of snakes are combined in a consistent framework for DLM road network adaptation. One important modification redefines the standard internal energy and thus the geometrical model of the snake in order to prevent changes in shape or position not caused by significant features in the image energy. For this purpose, the initial shape is utilized creating template-like snakes with the ability of local adaptation. This is one crucial point towards the applicability of the entire method considering the strongly varying significance of the ALS features. Other concepts related to snakes are integrated which enable our method to model network and ribbon-like characteristics simultaneously. Additionally, besides ALS road features information about context objects, such as bridges and buildings, is introduced as part of the image energy to support the optimisation process. Meaningful examples are presented that emphasize and evaluate the applicability of the proposed method. 相似文献
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秦直道旅游开发问题探讨 总被引：1，自引：0，他引：1
秦直道是古代连接中原地区和北方少数民族地区的一条重要纽带,它是秦帝国传递中央政令和传播中原文化的重要通讯带,也是秦始皇为抵御匈奴、调动兵力和物资的一条战略要道,在历史上起到了极其重要的作用.通过对秦直道及其现阶段旅游资源开发现状的介绍和在对秦直道旅游资源开发的可行性综合评价与分析的基础上,提出秦直道旅游资源开发的初步构想. 相似文献
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《Proceedings of the Geologists' Association. Geologists' Association》2017,128(1):146-150
This paper presents a new interpretation of the sequence of events in Glen Roy and vicinity during the Loch Lomond Stadial that can be inferred from a detailed varve record constructed by Palmer et al. (2010). 300 years of Younger Dryas glacier advance in the Scottish Highlands are recorded by very thin varves formed in an ice-dammed lake up to 35 km long. At a varve site now occupied by Loch Laggan the lake stood permanently at 260 m, but in Glen Roy varves were also laid down in a lake at 325 m and, later, 350 m caused by glacier advance. Initial ice retreat recorded by a gradual increase in varve thickness was soon followed by much thicker varves. The varve sequences are interrupted by a sand bed caused by sudden drainage of the 350 m lake. The major varves of the Glen Roy sequence show that storminess was still increasing in intensity at least 160 years after glacier retreat had begun. At the Loch Laggan site 15 cm of deformed sediments register an earthquake that produced 3 m faulted uplift of all three Glen Roy shorelines, a response to the abrupt removal of 5 km3 of water when the 260 m lake was catastrophically drained by jökulhlaup. The deformed sediments are immediately followed by varves deposited in a local lake, ice-dammed lake sedimentation now having ceased, having lasted more than 460 years. 相似文献
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历史地理视角下丝绸之路空间格局及影响研究 总被引：1，自引：0，他引：1
已有的“一带一路”相关研究已逐步引起了学界对历史文化资源于今日发展影响的关注,然而作为“一带一路”倡议的历史依托和出发点,丝绸之路相关量化研究仍处于起步阶段。从文明的角度来说,如何认识丝绸之路是当代中国理解全球的关键。运用OLS、Logistic回归等手段,定量探讨了丝绸之路路线的形成动因以及其对历史及当代的影响。结果表明：① 丝绸之路道路密度分布总体处于波动状态,在以罗马、长安、大都为代表的交通网络起始点以及撒马尔罕、塔什干为代表的内线重要中转枢纽处密度数值大幅提高。② 作为商业贸易通道,丝绸之路路线选择影响最大的因素是地理因子,主要倾向于低坡度、高起伏度的地区,这一点在中亚复杂山地地形中表现得尤为明显。③ 丝绸之路的开辟与通畅,对当时社会经济、城市发展起到了显著的作用。丝绸之路道路密度同距最近海岸距离、纬度、历史文明指数等指标一道构成了古代城市分布的主要影响因素。④ 丝绸之路对区域经济发展的正面影响具有一定的持续性,其对今日经济的发展仍起着难以否认的支撑作用。丝绸之路道路密度每增加1%,所在区域夜间灯光指数增加0.373。本文通过横跨历史学、地理学、经济学的探索能够很好地提供差异化理论视角和技术手段助益,为相关研究的开展起到一定的参考与启发作用,同时也为“一带一路”相关理论的完善提供理论支撑与历史证明。 相似文献
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《更路簿》是一本海南渔民往来南海诸岛礁的航海手册,记录了海南岛渔民命名南海岛礁的地理名称136处,这些南海地名生动地反映了南海岛礁的自然地理及文化特征。该文论述了《更路簿》与《针路簿》的起源与差别,探讨了《更路簿》中的岛礁分类与命名方式,将《更路簿》中的南沙岛礁的名称及其释义集成在一起,并对照谷歌地球进行定位与校核。依据名从主人的地名学规则,海南渔民是最早探索、发现、命名南海岛礁并对其不间断地开发的经营者,因此为南海诸岛是中国的固有领土提供有力佐证。该文从南海的季风洋流对航海的影响分析,探讨了帆船时代居住在季风海流两侧国家的人民探索发现南海诸岛的局限性。 相似文献
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秦蜀古道是中国古代一条国家级大道,是中国线性文化遗产的重要组成部分。随着测绘技术的飞速发展,测绘在文物保护中发挥了越来越重要的作用。本文以陕西省境内的秦蜀古道遗产调查为例,解决了以下主要关键技术:1)引入三维激光扫描技术快速高效地获取不易到达的秦蜀古道重要遗产的精确信息;2)应用倾斜摄影测量技术,精细构建秦蜀古道重点段地形模型,直观展现秦蜀古道地形地貌特征;3)利用三维地理信息系统技术,研发秦蜀古道管理信息系统,解决调查成果数据量大,检索管理及分析应用中的难题。通过对秦蜀古道遗产调查中的关键测绘技术开展研究,旨在为秦蜀古道遗产的保护提供技术支撑。 相似文献