A reinterpretation of Scottish ‘hummocky moraine’ and its significance for the deglaciation of the Scottish Highlands during the Younger Dryas or Loch Lomond Stadial

1993 ◽  
Vol 130 (3) ◽  
pp. 301-318 ◽  
Author(s):  
Matthew R. Bennett ◽  
Geoffrey S. Boulton

AbstractThe aim of this paper is to demonstrate that much of the ‘hummocky moraine’ present within the northern part of the LochLomond Readvance ice cap formerly situated in the North West Scottish Highlands may be interpreted as suites of ice-front moraines deposited during active decay. These landforms can be used to reconstruct ice cap decay, whichleads to important insights into the shrinking form of the ice cap and associated environmental conditions. Evidence has been collected from 10803 airphotographs and from detailed field survey. It is presented at three spatial scales.

1896 ◽  
Vol 3 (4) ◽  
pp. 167-174 ◽  
Author(s):  
Peter Macnair

In the following paper I propose to give an account of some observations upon the structure and succession of the rocks of the Southern Highlands. By the term Southern Highlands I mean that part of the Scottish Highlands lying immediately to the north-west of the great line of fault separating the older rocks of the former area from the younger Old Red Sandstone series of the low grounds.


2012 ◽  
pp. 566-588
Author(s):  
Paul Grace ◽  
Danny Hughes ◽  
Geoff Coulson ◽  
Gordon S. Blair ◽  
Barry Porter ◽  
...  

Grid computing is becoming increasingly pervasive; sensor networks and mobile devices are now connected with traditional Grid infrastructure to form geographically diverse complex systems. Applications of this type can be classified as the Pervasive Grid. In this chapter we examine how traditional Grid technologies and middleware are inherently unsuited to address the challenges of extreme heterogeneity and fluctuating environmental conditions in these systems. We present Gridkit, a configurable and reconfigurable reflective middleware that leverages overlay networks and dynamic software in response to the requirements of the Pervasive Grid. We also illustrate how Gridkit has been used to deploy a flood monitoring application at a river in the north west of England; this demonstrates both the flexibility Gridkit provides, and how dynamic adaptation optimises performance and resource consumption.


Virus isolations Mosquito collections obtained during most field trips to the north-west of Western Australia have been processed for virus isolation. Until 1985, virus isolation was undertaken by intracerebral inoculation of suckling mice, but this was then replaced by cell culture using C6/36 mosquito, PSEK, BHK and Vero cells. The use of cell culture has significantly reduced the overall virus isolation rate by largely excluding arboviruses, rhabdoviruses and most bunyaviruses, but is as effective as suckling mice for the isolation of flaviviruses and alphaviruses. MVE virus has been isolated every year that significant numbers of adult mosquitoes have been processed except 1983 (Broom et al. 1989; Broom et al. 1992; Mackenzie et al. 1994c). Isolations of MVE, Kunjin and other flaviviruses are shown in Table 8.2. There was a strong correlation between the number of virus isolates in any given year and the prevailing environmental conditions. Thus those years with a heavy, above average wet season rainfall and subsequent widespread flooding yielded large numbers of virus isolates (1981, 1991, 1993) compared with years with average or below average rainfall and with only localized flooding. Although most MVE virus isolates were obtained from Culex annulirostris mosquitoes, occasional isolates were also obtained from a variety of other species, including Culex quinquefasciatus, Culex palpalis, Aedes normanensis, Aedes pseudonormanensis, Aedes eidvoldensis, Aedes tremulus, Anopheles annulipes, Anopheles bancroftii, Anopheles amictus and Mansonia uniformis (cited in Mackenzie et al. 1994b; Mackenzie and Broom 1995), although the role of these species in natural transmission cycles has still to be determined. Virus carriage rates in Culex annulirostris mosquitoes are shown in Table 8.3 for the Ord River area (Kununurra–Wyndham) and Balgo and Billiluna in south-east Kimberley. Very high mosquito infection rates were observed in those years with above average rainfall. Virus spread and persistence Stanley (1979) suggested that viraemic waterbirds, which are often nomadic, may generate epidemic activity of MVE in south-east Australia and in the Pilbara region. In an attempt to understand the genesis of epidemic activity better, our laboratory initiated a long-term study in the arid south-east Kimberley area at Billiluna and Balgo, two Aboriginal communities on the northern edge of the Great Sandy Desert. Occasional cases of Australian encephalitis had occurred in both communities (1978, 1981). The studies have clearly shown that MVE virus activity only occurs following very heavy, widespread rainfall both locally and in the catchment area of the nearby watercourse, Sturt Creek, which results in extensive flooding across its floodplain (Broom et al. 1992). Localized flooding is insufficient to generate virus activity. Two possible explanations can be proposed to account for the reappearance of MVE virus activity when environmental conditions are suitable: either virus can be reintroduced into the area by viraemic waterbirds arriving from enzootic areas further north; or virus may

1998 ◽  
pp. 133-135

1954 ◽  
Vol 2 (16) ◽  
pp. 423-428

AbstractMorsárjökull is a small outlet glacier of Vatnajökull, Iceland. Two outlet streams from the ice cap unite at the foot of a precipitous step and carry a well-developed medial moraine; the north-west glacier stream is fed by a steep ice fall, the south-eastern one has been fed only by avalanches since 1938.The movement of the glacier was measured and showed that the alternate dark and light ogives were one year’s movement apart. Their characteristics are described and tentative suggestions concerning their mode of origin are proposed.


1975 ◽  
Vol 14 (71) ◽  
pp. 267-274 ◽  
Author(s):  
R. S. Bradley

Equilibrium-line altitudes on the White Glacier, Axel Heiberg Island, and the north-west sector of the Devon Ice Cap are shown to be closely related to mean July freezing-level heights at nearby upper-air weather stations. An inverse relationship between July freezing-level heights and mass balance on the Devon Ice Cap is also shown. Reasons for such correlations are suggested and some limitations of the relationship are outlined. Recent lowering of the freezing level in July is discussed in relation to the theoretical “steady-state” equilibrium-line altitudes in the Canadian high Arctic. It is suggested that positive mass-balance years have predominated over a large part of northern Ellesmere Island and north-central Axel Heiberg Island since 1963, and some glaciological evidence supporting this hypothesis is given.


1971 ◽  
Vol 10 (59) ◽  
pp. 245-254 ◽  
Author(s):  
R. A. Souchez

AbstractThe north-west margin of the main ice cap in south-western Ellesmere Island is fringed by ice-cored moraines. The formation of these moraines seems to be more complex than simple upwarping of the foliation bands at the margin of the ice cap. At one locality, where outer and inner zones can be distinguished on the basis of lithological composition, debris in the outer zone is composed of material from farther back under the ice cap than debris in the inner zone. In another locality, localized ridges cross each other independently of the trend of the main ridge.The time required to obtain the quantity of debris forming the moraine at the ice surface is estimated to be between 65 and 300 years.


Author(s):  
A. Forster ◽  
P. R. N. Hobbs ◽  
R. J. Wyatt ◽  
D. C. Entwisle

AbstractIn March 1984 the British Geological Survey commenced an environmental geological study of parts of west Wiltshire and south east Avon for the Department of the Environment. The objective of this study was to collect the available geological data relevant to the area, and to present them as a series of thematic maps accompanied by a descriptive report and a database/archive of the data used.The output is intended to be used by land-use planners. It is designed simultaneously to be understandable by people not trained in geology and yet to contain detailed information required by specialists concerned with the environment and its development. The 14 maps which were produced describe themes which include solid lithostratigraphy, drift deposits, the inferred distribution of Great Oolite Freestone, the inferred distribution of fuller’s earth, groundwater, ground conditions in relation to groundwater, geotechnical properties of bedrock and superficial deposits, landslipped and cambered strata, distribution of slope angle, and mining.Although the task was primarily a desk study, it was found necessary to carry out a small amount of field survey to re-interpret the foundered strata to the north-west of Bath. This re-survey has been presented in a style consistent with the mapping of the rest of the study area. A fifteenth map showing the result of the re-interpretation of the foundered strata was produced as a supplement to the main report.This paper describes the methods and the results of this study and comments on the implications of the technique for land-use planning.


Author(s):  
Mike Searle

The Himalaya is the greatest mountain range on Earth: the highest, longest, youngest, the most tectonically active, and the most spectacular of all. Unimaginable geological forces created these spectacular peaks. Indeed, the crash of the Indian plate into Asia is the biggest known collision in geological history, giving birth to the Himalaya and Karakoram, one of the most remote and savage places on Earth. In this beautifully illustrated book, featuring spectacular color photographs throughout, one of the most experienced field geologists of our time presents a rich account of the geological forces that were involved in creating these monumental ranges. Over three decades, Mike Searle has transformed our understanding of this vast region. To gather his vital geological evidence, he has had to deploy his superb skills as a mountaineer, spending weeks at time in remote and dangerous locations. Searle weaves his own first-hand tales of discovery with an engaging explanation of the processes that formed these impressive peaks. His narrative roughly follows his career, from his early studies in the north west Himalaya of Ladakh, Zanskar and Kashmir, through several expeditions to the Karakoram ranges (including climbs on K2, Masherbrum, and the Trango Towers, and the crossing of Snow Lake, the world's largest ice cap outside polar regions), to his later explorations around Everest, Makalu, Sikkim and in Tibet and South East Asia. The book offers a fascinating first-hand account of a major geologist at work-the arduous labor, the eureka moments, and the days of sheer beauty, such as his trek to Kathmandu, over seven days through magnificent rhododendron forests ablaze in pinks, reds and white and through patches of bamboo jungle with hanging mosses. Filled with satellite images, aerial views, and the author's own photographs of expeditions, Colliding Continents offers a vivid account of the origins and present state of the greatest mountain range on Earth.


1970 ◽  
Vol 9 (57) ◽  
pp. 325-336 ◽  
Author(s):  
R.M. Koerner

Methods used in measuring the mass balance of the Devon Island ice cap are described. The use of dyes and melt trays is recommended in the superimposed-ice and firn zones of sub-polar glaciers. The north-west part of the ice cap was studied in most detail and has had a slightly negative net balance for the period 1961-66. An inverse relationship between mean net balance(bn)and elevation of the equilibrium line in the north-west part of the ice cap indicates that the mean net balance there would be zero with an equilibrium line at 920 m (±80 m) elevation. Accumulation on the ice cap is greatest in the south-east but the measurements suggest that the mean net balance there is similar to the mean net balance on the rest of the ice cap. It is concluded that the present accumulation pattern must have existed for several hundreds, and possibly thousands of years. A study of firn stratigraphy and of variations in the elevation of the firn and equilibrium lines indicates that between 1961 and 1966 only 1962 had a more negative mean net balance than the average value for the period 1934-60. During the same 26 year period the net balance at 1 787 m elevation has varied, but summer conditions do not appear to have changed significantly.


1971 ◽  
Vol 10 (59) ◽  
pp. 245-254 ◽  
Author(s):  
R. A. Souchez

AbstractThe north-west margin of the main ice cap in south-western Ellesmere Island is fringed by ice-cored moraines. The formation of these moraines seems to be more complex than simple upwarping of the foliation bands at the margin of the ice cap. At one locality, where outer and inner zones can be distinguished on the basis of lithological composition, debris in the outer zone is composed of material from farther back under the ice cap than debris in the inner zone. In another locality, localized ridges cross each other independently of the trend of the main ridge.The time required to obtain the quantity of debris forming the moraine at the ice surface is estimated to be between 65 and 300 years.


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