Book Review: Aeolian Geomorphology: An Introduction by Ian Livingstone and Andrew Warren,Longman, Harlow, 1996. No. of pages: xi+211. Price £25.99 (pb). ISBN 0-582-08704-X     

Graeme Butterfield 《地球表面变化过程与地形》1997,22(11):1083-1084

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U-Pb zircon systematics at Gruinard Bay, northwest Scotland: implications for the early orogenic evolution of the Lewisian complex     

Fernando Corfu  Alan Crane  Desmond Moser  Graeme Rogers 《Contributions to Mineralogy and Petrology》1998,133(4):329-345

The Gruinard Bay area of the mainland Lewisian complex comprises a metamorphosed suite of Archaean trondhjemites and minor granites enclosing remnants of older tonalitic gneiss and mafic to ultramafic enclaves. The U-Pb zircon dating yields ages of 2731 ±14 Ma and 2728 ±2 Ma for two trondhjemite and 2732 ±4 Ma for one granite sample, also revealing the presence of large amounts of inherited xenocrystic zircons. Although the region has been pervasively overprinted by retrogressive events in amphibolite to greenschist facies, the textural relations between biotite, hornblende, quartz and titaniferous minerals indicate that these minerals are pseudomorphs of pyroxene and high-Ti amphibole formed in hornblende-granulite facies. Structural relations link this metamorphism to a steep northeast-trending fabric coeval with the intrusion of the trondhjemites, dated at 2730 Ma. Dating of zircon in amphibolite and tonalite enclaves yields complex internal isotopic relations with apparent ages ranging from 2825 to 2740 Ma. This age range reflects new growth during the 2730 Ma metamorphic/metasomatic events, superimposed on older zircon phases which include combinations of xenocrystic cores, and magmatic and/or metamorphic growth phases whose mode of formation cannot clearly be resolved by imaging techniques (e.g. cathodoluminescence) alone. A pegmatitic vein that escaped the D₃ strain and related isotopic disturbances yields a precise age of 2792 ±2 Ma, which constrains to some degree the earliest orogenic events in the area. Age relationships displayed in the central block at Scourie–Badcall, and in the Gruinard Bay area indicate that petrogenetic events in both areas were comparable about 2800 Ma and that both areas underwent trondhjemitic magmatism about 2730 Ma. In contrast, at Gruinard Bay there is no isotopic evidence for a period of high-grade metamorphism and magmatism at 2490–2480 Ma that drastically affected the Scourie block indicating that at this stage the two regions occupied different levels of the crust. Received: 23 October 1997 / Accepted: 20 July 1998  相似文献   

Terror in the skies of Russia     

Graeme Poole 《Geology Today》2013,29(5):177-181

It was just another normal day for the residents of the Russian town of Chelyabinsk as they set off for work on Friday 15 February 2013. A rock less than 20 metres wide changed all that. A meteor weighing some 11 000 tonnes hit the Earth's atmosphere above the Ural Mountains with an estimated speed of 18 km/s (65 000 km/h). It exploded over Chelyabinsk with the force of 30 Hiroshima bombs, causing a shockwave to tear through the region and injuring over 1500 people. It was the biggest meteor strike in the last 100 years, and undoubtedly the most archived ever.  相似文献   

Erratum to: Influence of ocean–atmospheric oscillations on lake ice phenology in eastern North America     

R. Timothy Patterson  Graeme T. Swindles 《Climate Dynamics》2015,45(9-10):2963-2963

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Unreported bycatch in the New Zealand West Coast South Island hoki fishery     

Graeme Bremner  Peter Johnstone  Tracy Bateson  Philip Clarke 《Marine Policy》2009

There are recognised benefits to managing fisheries by individual transferable quotas (ITQs), but ITQs may increase incentives to discard fish.  相似文献   

Optical spectra of supernova remnant candidates in the Sculptor Group galaxy NGC 300     

William C. Millar  Graeme L. White  Miroslav D. Filipović  Jeffrey L. Payne  Evan J. Crawford  Thomas G. Pannuti  Wayne D. Staggs 《Astrophysics and Space Science》2011,332(2):221-239

We present moderate-resolution (<5 Å) long-slit optical spectra of 51 nebular objects in the nearby Sculptor Group galaxy NGC 300 obtained with the 2.3 meter Advanced Technology Telescope at Siding Spring Observatory, Australia. Adopting the criterion of [S?ii]_Total:Hα≥0.4 to confirm supernova remnants (SNRs) from optical spectra, we find that of 28 objects previously proposed as SNRs from optical observations, 22 meet this criterion with six showing [S?ii]_Total:Hα of less than 0.4. Of 27 objects suggested as SNRs from radio data, four are associated with the 28 previously proposed SNRs. Of these four, three (included in the 22 above) meet the criterion. In all, 22 of the 51 nebular objects meet the [S ii]_Total:Hα criterion as SNRs while the nature of the remaining 29 objects remains undetermined by these observations.  相似文献   

Effects of antifouling biocides to the germination and growth of the marine macroalga, Hormosira banksii (Turner) Desicaine     

Myers JH  Gunthorpe L  Allinson G  Duda S 《Marine pollution bulletin》2006,52(9):1048-1055

The International Maritime Organisation's (IMO) ban on the use of tributyltin in antifouling paints has inevitability increased the use of old fashioned antifoulants and/or the development of new paints containing 'booster biocides'. These newer paints are intended to be environmentally less harmful, however the broader environmental effects of these 'booster biocides' are poorly known. Germination and growth inhibition tests using the marine macroalga, Hormosira banksii (Turner) Desicaine were conducted to evaluate the toxicity of four new antifouling biocides in relation to tributyltin-oxide (TBTO). Each of the biocides significantly inhibited germination and growth of Hormosira banksii spores. Toxicity was in increasing order: diuron < zineb < seanine 211< zinc pyrithione < TBTO. However, the lack of knowledge on partitioning in the environment makes it difficult to make a full assessment on whether the four biocides tested offer an advantage over organotin paints in terms of environmental impact.  相似文献   

Can ecological and evolutionary arguments solve the riddle of the missing marine insects?     

Graeme D. Ruxton  & Stuart Humphries 《Marine Ecology》2008,29(1):72-75

We critically appraise the recent literature on the paucity of marine insects and conclude that this near‐absence does demand explanation; but this explanation is unlikely to be found in the suggested problems of depth for insect respiratory systems. We tentatively suggest some areas where further consideration may yield fruitful answers to this long‐standing evolutionary riddle.  相似文献   

Sedimentology,palaeoecology and geochronology of Marine Isotope Stage 5 deposits on the Shetland Islands,Scotland     

Adrian M. Hall  John E. Gordon  Graeme Whittington  Geoffrey A. T. Duller  Hendrik Heijnis 《第四纪科学杂志》2002,17(1):51-67

New stratigraphical, palynological and dating evidence is presented for pre‐Late Devensian/Weichselian sediments at Fugla Ness and Sel Ayre, Shetland. The Fugla Ness Peat rests on till and formed during an interglacial that saw the development of maritime heaths, with scattered trees and shrubs, including Pinus and possibly Ilex. A decline into stadial conditions is marked by overlying periglacial breccia and till. The Sel Ayre Organic Sands and Gravels lie between periglacial breccias and beneath till and appear to record a changing interstadial environment in which trees were absent and the vegetation comprised largely heaths, with Bruckenthalia, and grasslands. The Fugla Ness Peat is dated to 110+40/?35 ka by uranium series disequilibrium, suggesting that it formed during the Ipswichian/Eemian Interglacial (Marine Isotope Substage 5e). Luminescence ages of ca. 98–105 ka on intercalated sands within the Sel Ayre Organic Sands and Gravels place these deposits in Marine Isotope Substage 5c (Brørup Interstadial). The two sites provide the first detailed record of Marine Isotope Stage 5 environments on Shetland. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

Autonomous video camera system for monitoring impacts to benthic habitats from demersal fishing gear, including longlines     

Robert Kilpatrick  Graeme EwingTim Lamb  Dirk WelsfordAndrew Constable 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(4):486-491

Studies of the interactions of demersal fishing gear with the benthic environment are needed in order to manage conservation of benthic habitats. There has been limited direct assessment of these interactions through deployment of cameras on commercial fishing gear especially on demersal longlines. A compact, autonomous deep-sea video system was designed and constructed by the Australian Antarctic Division (AAD) for deployment on commercial fishing gear to observe interactions with benthos in the Southern Ocean finfish fisheries (targeting toothfish, Dissostichus spp). The Benthic Impacts Camera System (BICS) is capable of withstanding depths to 2500 m, has been successfully fitted to both longline and demersal trawl fishing gear, and is suitable for routine deployment by non-experts such as fisheries observers or crew. The system is entirely autonomous, robust, compact, easy to operate, and has minimal effect on the performance of the fishing gear it is attached to. To date, the system has successfully captured footage that demonstrates the interactions between demersal fishing gear and the benthos during routine commercial operations. It provides the first footage demonstrating the nature of the interaction between demersal longlines and benthic habitats in the Southern Ocean, as well as showing potential as a tool for rapidly assessing habitat types and presence of mobile biota such as krill (Euphausia superba).  相似文献