Geological photographs: historical magic or national record?     

GRAHAM McKENNA  ERIC ROBINSON 《Geology Today》1996,12(3):114-116

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Definition and character of the Regency Interglacial and Early-Middle Pleistocene stratigraphy in the King Valley, western Tasmania, Australia     

SEAN J. FITZSIMONS  ERIC A. COLHOUN  GUUS VAN DE GEER  ROBERT S. HILL 《Boreas: An International Journal of Quaternary Research》1990,19(1):1-15

Interpretation of weathered glacial and interglacial deposits in the lower King Valley suggests that the Early Pleistocene Thureau Formation is conformably overlain by the Regency Formation. Pollen analysis of the Regency Formation provides evidence of a new climatic stage, the Regency Interglacial. The interglacial deposit consists of humified peat overlain by drifted wood and leaves. The pollen analysis shows a transition from montane scrub rainforest to lowland temperate rainforest dominated by Lagarostrobos franklinii, Nothofagus cunninghamii and Phyllocladus aspleniifolius. Trace quantities of the species Quintinia psi-latispora and Gothanipollis perplexus , now both extinct in Tasmania, were also recorded. On the basis of intense chemical weathering and correlation with sediments that have a reversed magnetization the weathered glacial deposits of the Thureau Formation are thought to be older than 730,000 B.P. The eroded interglacial deposit rests on the weathered deposits and is buried by outwash gravels of the David Formation, which was deposited during an ice advance of the Middle Pleistocene Henty Glaciation (c. 150,000 B.P.). Comparison of the Regency site with a site 2 km to the south at Baxter Rivulet shows that the unconformity between the interglacial deposit and the overlying outwash gravel represents the erosion of the evidence for the Middle Pleistocene Moore Glaciation.  相似文献   

EUROPEAN SETTLEMENT AND DEVELOPMENT IN NORTH AMERICA. Edited by James R. Gibson     

ERIC PAWSON 《New Zealand geographer》1980,36(1):39-40

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Effects of waste disposal on groundwater and surface water     

ERIC C. BARRETT 《水文科学杂志》2013,58(2):273-283

ABSTRACT

Remote sensing has great, but largely unrealized, potential in operational hydrology especially in countries where conventional data are not adequate even to meet existing needs. It is argued in this paper, and illustrated with special reference to the monitoring of rainfall, that organizational, not physical, problems have been the most significant in limiting the spread of satellite remote sensing applications within the developing world. Looking to the future, the relative merits of tactical (“bottom up”) and strategic (“top down”) approaches for the promotion of satellite remote sensing for hydrology in such areas are outlined and discussed. It is concluded that existing and proposed IHP projects may proffer some suitable channels through which significant progress could be made.  相似文献   

Editorial     

TERRY COPPOCK  ERIC ANDERSON 《International journal of geographical information science》2013,27(4):301-302

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Atmospheric deposition to watersheds in complex terrain     

GARY M. LOVETT  JONATHAN J. BOWSER  ERIC S. EDGERTON 《水文研究》1997,11(7):645-654

Single collection stations for wet or bulk deposition are generally inadequate to describe atmospheric inputs to watersheds in complex terrain. Atmospheric deposition is delivered by wet, dry and cloud deposition processes, and these processes are controlled by a wide range of landscape features, including canopy type and structure, topographic exposure, elevation and slope orientation. As a result, there can be a very high degree of spatial variability within a watershed, and a single sampling point, especially at low elevation, is unlikely to be representative. Atmospheric inputs at the watershed scale can be calculated from the whole watershed mass balance if the outputs and within-watershed sources and sinks are known with sufficient accuracy. Alternatively, indices of atmospheric deposition such as Pb accumulation in the forest floor and SO²⁻₄ flux in throughfall can be used to characterize patterns of total deposition, and these indices can be used to model deposition to the entire watershed based on known landscape features such as elevation and canopy type. © 1997 John Wiley & Sons, Ltd.  相似文献   

Professor Barry Johnston     

PETER HOLLAND  ERIC PAWSON 《New Zealand geographer》1993,49(2):3-6

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Counterpoint     

ERIC ROBINSON 《Geology Today》1987,3(1):11-12

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Freshwater organisms that build stromatolites: a synopsis of biocrystallization by prokaryotic and eukaryotic algae   总被引：2，自引：0，他引：2  

PIERRE FREYTET  & ERIC P. VERRECCHIA 《Sedimentology》1998,45(3):535-563

In freshwater environments such as river and stream bottoms, rocks and submerged vegetation are covered with a biological felt (also called a periphyton, microbial mat, biofilm, etc.) that is susceptible to calcification. Compilation of an extensive bibliography and our own observations have allowed the identification of 44 species of Coccogonophyceae, 122 Hormogonophyceae, 2 Chrysophyceae, 35 Chlorophyceae, 3 Xanthophyceae, 2 diatoms, and 3 Rhodophyceae that grow on calcareous tufa and coat vegetation. Diverse genera include species that are also calcified but impossible to determine because they lack reproductive organs. Crystals have been described from 74 species in the literature and we have observed 53 others. They can be classified into 10 groups: (1) platelets on cell walls (Volvocales, analogues of coccolithophorids) (2) crystals in mucilage (Synechococcus, diatoms, Hydrurus) and calcified stalks (Oocardium) (3) sheaths containing crystals in the form of simple or three-branched needles, dendritic crystals, and crystals with box-work fabric (Geitleria, Scytonema) (4) sheaths containing calcite spherulites (5) stalks intersecting a large crystal (Cymbella) (6) micrite tubes (Phormidium, Schizothrix) (7) isolated rhombohedra (Zygnema, Scytonema), rhombohedra in clusters or chains (Nostoc parmelioides) (8) sparite platelets (Vaucheria) or isodiametric crystals (Scytonema, Chaetophora) (9) large crystals crosscut by many parallel filaments (Rivularia, Batrachospermum), and (10) fan-like crystals (Phormidium). These crystals can be arranged in clusters or form regular laminations. They can transform into isodiametric sparite crystals to form fan-like or radial palisadic structures. Knowledge of primary crystals and their diagenetic transformations is necessary to correctly interpret freshwater stromatolites. The latter always result from intense calcification and are a diagenetic transformation of a biological felt made of many prokaryotic and eukaryotic algal species, small invertebrates, and organic and mineral debris.  相似文献   

Last Glacial Maximum equilibrium-line altitude trends and precipitation patterns in the Sangre de Cristo Mountains, southern Colorado, USA     

KURT A. REFSNIDER  KEITH A. BRUGGER  ERIC M. LEONARD  JAMES P. McCALPIN  PHILIP P. ARMSTRONG 《Boreas: An International Journal of Quaternary Research》2009,38(4):663-678

Precipitation patterns during the Last Glacial Maximum (LGM) in the Rocky Mountains varied due to the influence of the continental ice sheets and pluvial lakes. However, no constraints have been placed on potential changes of southeasterly Gulf of Mexico-derived moisture that today contributes considerable precipitation to the easternmost ranges of the southern and middle Rocky Mountains. The Sangre de Cristo Mountains of southern Colorado are ideally situated to assess the relative importance of westerly and southeasterly-derived moisture during the LGM. Based on reconstructions of 30 palaeoglaciers in the Sangre de Cristo Mountains, we find that LGM equilibrium-line altitudes (ELAs) on the east side of the range were systematically 100–200 m lower than ELAs on the west side. The observed ELA pattern is strikingly similar to modern precipitation patterns in the study area, suggesting that southeasterly-derived precipitation had a significant influence on the mass balances of LGM glaciers.  相似文献