PHYSICAL PROPERTIES AND FORMATION OF FLUTES AT A POLYTHERMAL VALLEY GLACIER: MIDRE LOVÉNBREEN,SVALBARD     

SAM ROBERSON  BRYN HUBBARD  HAYLEY R. COULSON  IAN BOOMER 《Geografiska Annaler: Series A, Physical Geography》2011,93(2):71-88

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The earth's radiocarbon budget     

KEITH R. LASSEY  IAN G. ENTING  CATHY M. TRUDINGER 《Tellus. Series B, Chemical and physical meteorology》1996,48(4):487-501

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The development of a historical digital cadastral database†     

GARY J. HUNTER  IAN P. WILLIAMSON 《International journal of geographical information science》2013,27(2):169-179

With an ever-increasing number of land information systems being developed, there is a growing demand by users for systems which support the use of temporal data for time-based studies. System managers, however, may have difficulty responding to these calls because of the lack of available research to guide them in their task. This paper examines the simple method of storing and processing temporal graphical data by the addition of time-encoding attributes to data elements as required. To illustrate the technique, a historical digital cadastral database has been created which al lows users to display and report on the cadastral parcellation of a region at any time in the past. The method can also be widely applied to other data to assist a broad range of space/time-related studies.  相似文献   

The Regional Research Laboratory initiative A progress report     

IAN MASSER 《International journal of geographical information science》2013,27(1):11-22

Abstract

This paper outlines the origins and objectives of the four multidisciplinary Regional Research Laboratories (RRLs) established in Great Britain by the Economic and Social Research Council at Cardiff, Edinburgh, London and Newcastle, and describes the work undertaken in the first 6 months of the trial phase. The RRLs will have four main functions, viz., data management, software development, spatial analysis and research training. An example is given of the work undertaken at each RRL, viz., a general purpose system for the display and query of large spatially-referenced data sets, an integrated spatial database for south-east England, a health care planning information system for the County of Avon and a target marketing system. The trial phase of this initiative is then evaluated in terms of its laboratory, research and regional dimensions  相似文献   

Architecture of a coarse‐grained channel–levée system: the Rosario Formation,Baja California,Mexico     

IAN A. KANE  MASON L. DYKSTRA  BENJAMIN C. KNELLER  SACHA TREMBLAY  WILLIAM D. McCAFFREY 《Sedimentology》2009,56(7):2207-2234

Seafloor images of coarse‐grained submarine channel–levée systems commonly reveal complex braid‐plain patterns of low‐amplitude bedforms and zones of apparent bypass; however, mechanisms of channel evolution and the resultant channel‐fill architecture are poorly understood. At Playa Esqueleto the lateral relationships between various elements of a deep‐marine slope channel system are well‐exposed. Specifically, the transition from gravel‐dominated axial thalwegs to laterally persistent marginal sandstones and isolated gravel‐filled scours is revealed. Marginal sandstones pass into a monotonous thin‐bedded succession which built to form relatively low‐relief levées bounding the channel belt; in turn, the levées onlap the canyon walls. Three orders of confinement were important during the evolution of the channel system: (i) first‐order confinement was provided by the erosional canyon which confined the entire system; (ii) confined levées built of turbidite sandstones and mudstones formed the second‐order confinement, and it is demonstrated that these built from overspill at thalweg margins; and (iii) third‐order confinement describes the erosional confinement of coarse‐grained thalwegs and scours. Finer‐grained sediment was transported in suspension and largely was unaffected by topography at the scale of individual thalwegs. Facies and clast analyses of conglomerate overlying channel‐marginal scours reveal that they were deposited by composite gravity flows, which were non‐cohesive, grain‐dominant debris flows with more fluidal cores. These flows were capable of basal erosion but were strongly depositional; frictional freezing at flow margins built gravel levées, while the core maintained a more fluidal transport regime. The resultant architecture consists of matrix‐rich, poorly sorted levées bounding better‐sorted, traction‐dominated cores. The planform geometry is interpreted to have consisted of a low‐sinuosity gravel braid‐plain built by accretion around mid‐channel and bank‐attached bars. This part of the system may be analogous to fluvial systems; however, the finer‐grained sediment load formed thick suspension clouds, probably several orders of magnitude thicker than the relief of braid‐plain topography and therefore controlled by the levées and canyon wall confinement.  相似文献   

A new look at rifts     

LYNNE FROSTICK  IAN REID 《Geology Today》1987,3(5):122-126

Rift valleys have always enthralled geologists. They are the rents in the Earth's crust produced when continental plates pull apart. Besides telling us something about the evolution of our planet, they also act as topographic sumps in which parts of the sedimentary record of Earth history are often best preserved. Yet our understanding of how, where, and why rifts form has only recently come of age with new models of structure and sedimentation.  相似文献   

COMMENTARY: IODINE AND NEANDERTALS     

IAN TATTERSALL 《Geographical review》2002,92(1):94-96

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The Teton Dam: rhyolite foundation + loess core = disaster   总被引：1，自引：0，他引：1  

IAN SMALLEY 《Geology Today》1992,8(1):19-22

The Teton Dam was a large embankment dam built in Idaho, USA, in 1975. It failed catastrophically in 1976. Two major causes of failure were the fissured rhyolite terrain on which the dam was built and the brittle permeable loess used for the core. Thus two geological factors combined to produce an engineering disaster. The complex of factors involved in the failure is still being discussed by engineers and geologists.  相似文献   

A late Quaternary bio- and climatostratigraphy for marine sediments in the north-central part of the North Sea     

REX HARLAND  DIANE M. GREGORY  MURRAY J. HUGHES  IAN P. WILKINSON 《Boreas: An International Journal of Quaternary Research》1978,7(2):91-96

BOREAS Harland, R., Gregory, Diane M., Hughes, M. J. & Wilkinson, I. P. 1978 06 01: A late Quaternary bio- and climatostratigraphy for marine sediments in the north-central part of the North Sea. Boreas, Vol. 7, pp. 91–96. Oslo. ISSN 0300–9483.
Micropalaeontological studies of three boreholes in the north-central North Sea have led to the erection of a bio- and climatostratigraphy for the area. Palaeoenvironmental interpretations have depended largely upon oceanographic concepts and changes in the micropalaeontological assemblages have been related to postulated alterations in water mass regimes. The biostratigraphy can then be utilized as a climatostratigraphy since such water mass changes are most probably linked to alterations in the circulation of the North Atlantic, and in particular to the positions of the climatically important North Atlantic Current and Polar Front. The North Sea sequences are compared to similar sections in Europe and related to the commonly accepted standard chronostratigraphy.  相似文献   

Phonolitic Diatremes within the Dunedin Volcano, South Island, New Zealand   总被引：2，自引：2，他引：2  

PRICE  RICHARD C.; COOPER  ALAN F.; WOODHEAD  JON D.; CARTWRIGHT  IAN 《Journal of Petrology》2003,44(11):2053-2080

The Port Chalmers Breccia is a vent-filling, clastic volcanicunit exposed within the Miocene Dunedin Volcano of South Island,New Zealand. Clasts (up to in excess of 1 m but generally <20cm) are supported in ash and fine lapilli of phonolitic (ne-benmoreiteor tephro-phonolite) composition and the dominant clast type(55 to almost 100%) is also phonolitic. Less abundant lithologiesinclude ne-normative basalt (basanite), hawaiite, mugeariteand trachyandesite, syenites and microsyenites, coarse-grainedmafic (gabbros) and ultramafic rocks (pyroxenites, hornblendites),schists and sediments. The breccias were emplaced as diatremesassociated with localized, but highly explosive, eruptive eventsin which mantle-derived CO₂ was an important component. Thesyenitic and ultramafic clasts could represent intrusive suitesproduced by crystal fractionation acting on parental ne-benmoreitemagmas that may themselves have been derived by crystal fractionationfrom basanitic precursors. An alternative variation on thismodel is that the parental ne-benmoreites were generated throughpartial melting of an alkalic igneous underplate. Sr, Nd andPb isotopic compositions are strikingly similar to those ofintraplate igneous rocks, ranging in age from 100 to less than10 Ma, from elsewhere in the South Island, and New Zealand'ssub-Antarctic islands, the south Tasman Sea and the Ross Searegion. This regional, HIMU-influenced, isotopic signature isbelieved to be derived from within the lithospheric mantle. KEY WORDS: phonolite; diatreme; nepheline syenite; Dunedin Volcano; alkalic rocks; fractional crystallization  相似文献