P-Wave Residual Differences and Inferences on an Upper Mantle Source for the Silent Canyon Volcanic Centre, Southern Great Basin, Nevada     

William Spence 《Geophysical Journal International》1974,38(3):505-523

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On the behaviour of dynamic contributing areas and flood frequency curves in North American Prairie watersheds     

Eghbal Ehsanzadeh  Christopher Spence  Garth van der Kamp  Brian McConkey 《Journal of Hydrology》2012

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Hatton Bank (northwest U.K.) continental margin structure   总被引：1，自引：0，他引：1  

R.S. White  G. K. Westbrook  S.R. Fowler  G.D. Spence  P.J. Barton  M. Joppen  J. Morgan  A.N. Bowen  C. Prestcott  M.H.P. Bott 《Geophysical Journal International》1987,89(1):265-272

Summary. The continent-ocean transition near Hatton Bank was studied using a dense grid of single-ship and two-ship multichannel seismic (mcs) profiles. Extensive oceanward dipping reflectors in a sequence of igneous rocks are developed in the upper crust across the entire margin. At the landward (shallowest) end the dipping reflectors overlie continental crust, while at the seaward end they are formed above oceanic crust. Beneath the central and lower part of the margin is a mid-crustal layer approximately 5 km thick that could be either stretched and thinned continental crust or maybe newly formed igneous crust generated at the same time as the dipping reflector sequence. Beneath this mid-crustal layer and above a well defined seismic Moho which rises from 27 km (continental end) to 15 km (oceanic end) across the margin, the present lower crust comprises a 10–15 km thick lens of material with a seismic velocity of 7.3 to 7.4 km/s. We interpret the present lower crustal lens as underplated igneous rocks left after extraction of the extruded basaltic lavas, A considerable quantity of new material has been added to the crust under the rifted margin. The present Moho is a new boundary formed during creation of the margin and cannot, therefore, be used to determine the amount of thinning.  相似文献   

Buchbesprechungen     

S. Haussühl  K. H. Wedepohl  H. Saalfeld  W. E. Petrascheck  J. C. H. Spence  Gabrielle Donnay  A. Preisinger 《Mineralogy and Petrology》1978,25(1):71-76

Ohne Zusammenfassung

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Book reviews

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Employment and worktravel in a selection of English inner cities     

Martin Frost  Nigel Spence 《Geoforum》1981,12(2):107-160

The inner parts of many of the western world's metropolitan areas are currently suffering such drastic decline that many governments are attempting to rejuvenate their economic fortunes This is the context in which the present study is set, focusing attention on five major English cities — London, Manchester, Birmingham, Nottingham and Leicester — and using census employment and worktravel data for small areas. The study first reports on the relationships between the skills offered by residents, both male and female, and those demanded by employers in inner city areas. In addition to the consideration of the detailed variety of manufacturing and servicing activities taking place, an examination of the office and non-office components of both is undertaken. The second main aspect of the study considers the patterns of worktravel movement linking the places of residence and workplaces so described. The research concludes with a view on the policy implications of the results in the light of the overall context of the rejuvenation of inner city areas.  相似文献   

Comparing Loss Estimation with Observed Damage: A Study of the 1999 Kocaeli Earthquake in Turkey   总被引：4，自引：0，他引：4  

Robin Spence  Julian Bommer  Domenico del Re  Juliet Bird  Nuray Aydinoğlu  Shigeko Tabuchi 《Bulletin of Earthquake Engineering》2003,1(1):83-113

Loss estimation from future earthquakes is of growing importance in planning earthquake protection strategies in high-risk areas. Loss models based on the spectral displacement approach are now widely used because of generally acknowledged deficiencies in earlier approaches using macroseismic intensity or peak ground-motion parameters. However, there has been to date rather little earthquake damage data by which the new generation of models can be assessed and which can be used to calibrate the parameters involved. The availability of several detailed damage surveys carried out following the 1999 Kocaeli earthquake in Turkey, provides a rare opportunity for such an assessment. In this paper the losses which would be predicted from two different approaches to loss assessment – one using predicted macroseismic intensity, the other using the spectral displacement method – are compared with actual observed losses in the Kocaeli event at two different locations where surveys were carried out. One of these sites was very close to the surface fault rupture (< 3 km distance), the other at a distance of about 4.5 km. It is shown that the predictive methods available generally overestimated the losses at these distances, and a number of possible reasons for these discrepancies are considered. The sensitivity of loss estimates to variations in the key parameters governing the estimation in each case are explored, in particular with respect to modifications in the parameters of the attenuation relationships and the vulnerability parameters. The implications of these results for estimating future losses are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

The Global Climate Observing System (GCOS)     

Thomas Spence  John Townshend 《Climatic change》1995,31(2-4):131-134

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基于NEESgrid网络的子结构拟动力实验:Mini-MOST实验     

杨鸥  杨广强  B.E. Spence  欧进萍 《地震工程与工程振动》2006,26(6):44-49

美国国家科学基金(US National Sc ience Foundation,简称NSF)资助研制开发的地震工程模拟网络(Network for Earthquake Engineering S imu lation,简称NEES)包括15个分布在不同地点的设备站点,并使用NEESgrid网络相互连接。NEESgrid是一个先进的网络设施,它为地震工程研究,尤其是多地点的子结构拟动力实验(Mu lti-site Substructure Pseudo-dynam ic,缩写为MS-PSD)提供了丰富的工具。本文首先简单地介绍了NEES和NEESgrid,然后使用了一个小尺寸的模型实验(M in i-MOST)演示了利用NEESgrid进行MS-PSD实验的过程。实验原型为一个单层二跨的框架结构,实验将该结构划分为两个实验子结构和一个模拟子结构。实验中,这三个子模块使用一个基于M atlab仿真协调程序SIMCOR进行协调,实验的每一步,SIMCOR发送位移请求给各个子模块并接收各子模块恢复力反馈,同时使用a-OS方法计算结构反应以及下一步的位移。实验结果与分析结果吻合相当好,展示了NEESgrid在多地点远程拟动力实验方面的能力。  相似文献   

Preface     

Robin Spence  Benoit Le Brun 《Bulletin of Earthquake Engineering》2006,4(4):319-321

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Patterns of basin fill in Triassic turbidites of the Nanpanjiang basin: implications for regional tectonics and impacts on carbonate‐platform evolution          下载免费PDF全文

Daniel J. Lehrmann  Daniel H. Chaikin  Paul Enos  Marcello Minzoni  Jonathan L. Payne  Meiyi Yu  Alexa Goers  Tanner Wood  Paula Richter  Brian M. Kelley  Xiaowei Li  Yanjiao Qin  Lingyun Liu  Gang Lu 《Basin Research》2015,27(5):587-612

The Nanpanjiang Basin occurs in a key position for resolving controversies of basin tectonics and patterns of plate assembly at the junction between south China and Southeast Asian plates. Paleocurrent measurements indicate that siliciclastic turbidites in the basin were sourced by the Precambrian Jiangnan uplift to the northeast, the Precambrian Yunkai uplift to the southeast and the Triassic Songma suture to the south. Detrital zircon geochronology reveals Archean (2500 Ma), Paleoproterozoic (1800–1900 Ma), Neoproterozoic (900–1000 Ma) and Paleozoic (420–460 Ma) ages consistent with derivation from the Jiangnan and Yunkai uplifts. A large Permian‐Triassic peak of 250 Ma is present in the southern basin and attenuates northward suggesting derivation from an arc developed along the Songma suture. Sandstone QFL compositions average 65/12/23% and plot in the recycled orogen field except for a few samples in the southern basin that fall in the dissected arc field. The compositions are consistent with derivation from Precambrian basement that includes orogenic complexes. In the southern basin, Middle Triassic turbidites contain greater lithics and feldspars and Lower Triassic turbidites have volcaniclastic composition consistent with derivation from a southerly arc. Our preferred interpretation is evolution from remnant basin to a large peripheral foreland with southward subduction and convergence with Indochina along the Songma suture. The previously proposed Dian‐Qiong zone is not a suture as its map location places it within carbonate platforms bounded by identical stratigraphy. The Nan‐Uttaradit zone is too distant to have provided voluminous siliciclastic flux to the basin. The Nanpanjiang Basin provides an example of the evolution of an exceptionally large foreland with far‐field rejuvenation of Precambrian uplifts and carbonate platforms that were significantly influenced by siliciclastic flux. The timing and pattern of turbidite basin fill impacted platform evolution by enabling margin progradation in areas proximal to siliciclastic sources, whereas platforms distant from sources were driven to aggradation and extreme relief with large‐scale gravitational sector collapse.  相似文献