SEASONAL VARIABILITY AND SIMULATION OF GROUNDWATER FLOW IN A PRAIRIE WETLAND     

PHILIP J. GERLA  RONALD K. MATHENEY 《水文研究》1996,10(7):903-920

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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   

Processes of flood‐triggered detrital layer deposition in the varved Lake Mondsee sediment record revealed by a dual calibration approach          下载免费PDF全文

LUCAS KÄMPF  ACHIM BRAUER  TINA SWIERCZYNSKI  MARKUS CZYMZIK  PHILIP MUELLER  PETER DULSKI 《第四纪科学杂志》2014,29(5):475-486

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Modelling of water quality processes in lakes and reservoirs. II     

J. PHILIP O'KANE 《水文科学杂志》2013,58(2):147-150

ABSTRACT

The snowmelt runoff process from small basins is discussed. A differentiation is made between overland flow in the snowpack and groundwater flow induced by infiltrating meltwater. The effect of variations of the snowmelt intensity on streamflow is studied. It is shown that the runoff is high from the first day of snowmelt runoff if the streamflow is caused by overland flow, and that there are pronounced peaks every day, which almost correspond with the snowmelt intensity during daytime. Streamflow originating from groundwater, on the other hand, increases continuously during the snowmelt and shows only small daily peaks in the flow. Simultaneous overland and groundwater flow are also discussed. Observed runoff hydrographs from small basins are analysed in some detail. For the open fields studied the runoff shows the typical character of overland flow. For a rather large forested area the surface runoff also constitutes an important part of the runoff, but the groundwater baseflow is considerable.  相似文献   

Early Last Interglacial palaeoenvironments in the western Baltic Sea: benthic foraminiferal stable isotopes and diatom‐based sea‐surface salinity     

KAREN LUISE KNUDSEN  HUI JIANG  PETER KRISTENSEN  PHILIP L. GIBBARD  HEIKKI HAILA 《Boreas: An International Journal of Quaternary Research》2011,40(4):681-696

Knudsen, K. L., Jiang, H., Kristensen, P., Gibbard, P. L. & Haila, H. 2011: Early Last Interglacial palaeoenvironments in the western Baltic Sea: benthic foraminiferal stable isotopes and diatom‐based sea‐surface salinity. Boreas, 10.1111/j.1502‐3885.2011.00206.x. ISSN 0300‐9483. Stable isotopes from benthic foraminifera, combined with diatom assemblage analysis and diatom‐based sea‐surface salinity reconstructions, are used for the interpretation of changes in bottom‐ and surface‐water conditions through the early Eemian at Ristinge Klint in the western Baltic Sea. Correlation of the sediments with the Eemian Stage is based on a previously published pollen analysis that indicates that they represent pollen zones E2–E5 and span ～3400 years. An initial brackish‐water phase, initiated c. 300 years after the beginning of the interglacial, is characterized by a rapid increase in sea‐surface and sea‐bottom salinity, followed by a major increase at c. 650 years, which is related to the opening of the Danish Straits to the western Baltic. The diatoms allow estimation of the maximum sea‐surface salinity in the time interval of c. 650–1250 years. After that, slightly reduced salinity is estimated for the interval of c. 1250–2600 years (with minimum values at c. 1600–2200 years). This may be related to a period of high precipitation/humidity and thus increased freshwater run‐off from land. Together with a continuous increase in the water depth, this may have contributed to the gradual development of a stratified water column after c. 1600 years. The stratification was, however, particularly pronounced between c. 2600 and 3400 years, a period with particularly high sea‐surface temperature, as well as bottom‐water salinity, and thus a maximum influence of Atlantic water masses. The freshwater run‐off from land may have been reduced as a result of particularly high summer temperatures during the climatic optimum.  相似文献   

Glacial meltwater erosion and sedimentation as evidence for multiple glaciations in west Wales     

NEIL F. GLASSER  JAMES L. ETIENNE  MICHAEL J. HAMBREY  JEREMY R. DAVIES  RICHARD A. WATERS  PHILIP R. WILBY 《Boreas: An International Journal of Quaternary Research》2004,33(3):224-237

This article presents the results of a geomorphological and sedimentological investigation of former glacial meltwater drainage in the region of the lower Afon Teifi, one of the major rivers of southwest Wales. Former drainage characteristics in the region are reconstructed concentrating on palaeo-drainage routes associated with successive Pleistocene glaciations and their role in the Quaternary evolution of the lower Teifi. Mapping of these features throughout a c. 100 km ² area reveals a complex evolution in the establishment of the present-day drainage system, with evidence for the following surface channel types: (i) type 1 channels of primary subglacial origin cut during the late Devensian (late Wisconsinan/late Weichselian) glaciation; (ii) type 2 channels representing either pre-late Devensian subaerial fluvial run-off, unconnected to the course of the preglacial Afon Teifi, or originating as subglacial chute channels; (iii) type 3 channels developed as subglacially modified pre-late Devensian tributaries of the Afon Teifi. Two further features are also described: (iv) type 4 channels are drift-plugged abandoned preglacial courses of the Afon Teifi, and (v) type 5 channels formed as lateglacial and post-late Devensian gorges which bypass type 4 channels. A relative chronostratigraphy based on channel geomorphology and sedimentology reveals an evolutionary sequence considerably more complicated than identified in previous studies, with extensive modification of the lower Afon Teifi region by glacial meltwater during at least two periods of Pleistocene glaciation.  相似文献   

Late Middle Pleistocene glaciation in East Anglia, England   总被引：1，自引：0，他引：1  

PHILIP L. GIBBARD  ANTTI H. PASANEN  RICHARD G. WEST  JUHA PEKKA LUNKKA  STEVE BOREHAM  KIM M. COHEN  CHRISTOPHER ROLFE 《Boreas: An International Journal of Quaternary Research》2009,38(3):504-528

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Origins of Large Volume Rhyolitic Volcanism in the Antarctic Peninsula and Patagonia by Crustal Melting   总被引：10，自引：1，他引：10  

RILEY  TEAL R.; LEAT  PHILIP T.; PANKHURST  ROBERT J.; HARRIS  CHRIS 《Journal of Petrology》2001,42(6):1043-1065

Voluminous rhyolitic volcanism along the palaeo-Pacific marginof Gondwana was marked by three principal episodes of magmatism.The first of these ( V₁) is essentially coincident with themain episode of Karoo–Ferrar magmatism at  相似文献   

What status for the Quaternary?   总被引：3，自引：0，他引：3  

PHILIP L. GIBBARD  ALAN G. SMITH  JAN A. ZALASIEWICZ  TIFFANY L. BARRY  DAVID CANTRILL  ANGELA L. COE  JOHN C. W. COPE  REW S. GALE  F. JOHN GREGORY  JOHN H. POWELL  PETER F. RAWSON  PHILIP STONE  COLIN N. WATERS 《Boreas: An International Journal of Quaternary Research》2005,34(1):1-6

The status of the Quaternary, long regarded as a geological period effectively coincident with the main climatic deterioration of the current Ice Age, has recently been questioned as a formal stratigraphic unit. We argue here that it should be retained as a formal period of geological time. Furthermore, we consider that its beginning should be placed at the Gauss-Matuyama magnetic chron boundary at about 2.6 Ma, rather than at its current position at about 1.8 Ma. The Quaternary would be formally subdivided into the Pleistocene and Holocene epochs. The global chronostratigraphical correlation table proposed is enclosed at the back of this issue.  相似文献   

Interior cratonic basins of Africa: relation to continental break-up and role of mantle convection   总被引：1，自引：0，他引：1  

ROXBY W. Hartley  PHILIP A. Allen 《Basin Research》1994,6(2-3):95-113

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