Temperaturen und Drucke bei der regionalen Metamorphose: Prinzipielle und praktische Hinweise     

Prof. Dr. Helmut G. F. Winkler 《International Journal of Earth Sciences》1976,65(1):874-885

The author's concept (1970, 1974) of evaluating metamorphic conditions is explained on the basis of most recent petrologic data. The major points treated are:

1. Instead of usual petrographic mapping, petrographic work in the field is aimed at specific “targets”, i.e., rock compositions. This is so because only specific rocks may give petrogenetically relevant information in the four metamorphic grades.
2. There are very many mineral reactions in metamorphism but only a few are petrogenetically significant. These are important to know, and they are graphically demonstrated. Any mineral assemblage that is formed by a significant mineral reaction must be verified as a paragenesis of mutually contacting minerals. Only such parageneses deserve to be mapped in the field as isograds or isoreactiongrads.
3. Crossing isograds or isoreactionsgrads provide data on temperature and pressure during metamorphism for that part of a metamorphic terrane where the crossing has been observed.
4. The sequence of isograds or isoreaction-grads may be a pressure indicator. Moreover, such a sequence provides geodynamic information whether a larger metamorphic area has been lifted up evenly or has been tilted while it was uplifted after metamorphism.

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Zur Erstellung von Wassergütemodellen für Talsperren mittels rekursiver Schätzverfahren     

A. Gnauck  J. Wernstedt  W. Winkler 《洁净——土壤、空气、水》1975,3(4):381-384

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Buchbesprechungen     

A. Hörler  R. Braun  E. Winkler  F. Zehender  E. Märki  R. Germanier 《Aquatic Sciences - Research Across Boundaries》1959,21(2):265-270

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Revised palaeoclimatic significance of Mueller Glacier moraines,Southern Alps,New Zealand          下载免费PDF全文

Natalya V. Reznichenko  Tim R. H. Davies  Stefan Winkler 《地球表面变化过程与地形》2016,41(2):196-207

A sequence of Late Holocene moraines on the foreland of the Mueller Glacier, Southern Alps, New Zealand, forms part of a local moraine‐age database used to establish a regional glacier chronology and subsequently to investigate potential intra‐hemispheric and global climate forcing mechanisms. We present new sedimentological and geomorphological evidence that a set of these moraine ridges, previously considered to represent individual advances, constitutes a single moraine complex (the ‘Mueller Memorial Moraine’) formed by supraglacial transport of a large volume of landslide debris to the glacier terminus. Because a moraine formed in this way is not necessarily associated with an advance triggered by a climate event, we question the palaeoclimatic significance of the Mueller Memorial Moraine, as well as that of other moraines in comparable settings. Our findings suggest that the mode of formation and glacio‐dynamical context of moraines whose ages contribute to existing palaeoclimate reconstructions need to be re‐examined in order to assess the reliability of these reconstructions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

A new scenario framework for climate change research: the concept of shared climate policy assumptions     

Elmar Kriegler  Jae Edmonds  Stéphane Hallegatte  Kristie L. Ebi  Tom Kram  Keywan Riahi  Harald Winkler  Detlef P. van Vuuren 《Climatic change》2014,122(3):401-414

The new scenario framework facilitates the coupling of multiple socioeconomic reference pathways with climate model products using the representative concentration pathways. This will allow for improved assessment of climate impacts, adaptation and mitigation. Assumptions about climate policy play a major role in linking socioeconomic futures with forcing and climate outcomes. The paper presents the concept of shared climate policy assumptions as an important element of the new scenario framework. Shared climate policy assumptions capture key policy attributes such as the goals, instruments and obstacles of mitigation and adaptation measures, and introduce an important additional dimension to the scenario matrix architecture. They can be used to improve the comparability of scenarios in the scenario matrix. Shared climate policy assumptions should be designed to be policy relevant, and as a set to be broad enough to allow a comprehensive exploration of the climate change scenario space.  相似文献   

Diurnal Variations in the Characteristics of Cloud-to-Ground Lightning Activity in the Great Lakes Region of the United States     

Claudia K. Walters  Julie A. Winkler 《The Professional geographer》1999,51(3):349-366

Cloud-to-ground (CG) lightning observations for the warm seasons (May-September) of 1989 and 1990 were analyzed for the Great Lakes region in order to assess the diurnal variations in the lightning characteristics. Several parameters, including flash rate, the spatial extent of lightning activity, first stroke peak current, and the percentage of positive flashes, varied markedly over the course of the day. In contrast, other parameters, such as the frequency of lightning periods and the multiplicity of both negative and positive CG flashes, displayed little diurnal variation. A large degree of intraseasonal (i.e., month-to-month) variation was observed in the diurnal patterns for several of the lightning parameters.  相似文献   

Moraine Formation at an Advancing Temperate Glacier: Brigsdalsbreen, Western Norway     

Stefan Winkler  & Atle Nesje 《Geografiska Annaler: Series A, Physical Geography》1999,81(1):17-30

Owing to increased winter balances especially since AD 1988/89, almost all valley outlet glaciers of Jostedalsbreen in western Norway are experiencing the largest advance since that of the early 18th century, the regional "Little Ice Age" maximum. Brigsdalsbreen advanced 441 m between 1987 and 1997. By the end of this period, the glacier had reached the outlet of the proglacial lake Brigsdalsvatnet, ploughing into unfrozen, fine-grained, water-soaked glaciolimnic sediments from the lake bottom and forming frontal moraines. These moraines are characterised by a lack of internal structures and preferred fabric. Owing to the strong advance, the moraine morphology is constantly changing, leaving only temporary moraine ridges.
Observations made along the glacier front suggest that the formation of these moraines can best be described as "bulldozed moraines", since the term push moraine, commonly associated with advancing glaciers, should be restricted to permafront environments. Different processes involved in moraine formation at frontal and lateral glacier margins result from variations in proglacial sediment properties, microrelief and glacier dynamics. Among these processes, large boulders left in the proglacial areas are pushed forward, forming pressure ridges on the distal side. Some of the largest boulders ( c . 80–120 m³) are overturned or rotated by the glacier.  相似文献   

      

P. Herzsprung  K. Friese  G. Packroff  M. Schimmele  K. Wendt-Potthoff  M. Winkler 《洁净——土壤、空气、水》1998,26(5):253-262

The investigated coal mining lakes (ML 111, ML 117, and ML 107) in the Lusatian lignite mining district are extremely acidic. The concentrations of iron in these geogenic acidified lakes are orders of magnitude higher than in acidic bog lakes and softwater lakes acidified by atmospheric deposition. For the most part ferric iron was the predominant species by a Fe(III) to Fe(II) ratio of more than 10. Density stratification of the water column leads to vertical concentration gradients of ferrous iron. Extremely high concentrations of ferrous iron were found in the anoxic layers above the sediment of ML 111 and ML 107. High concentrations of Fe(II) were correlated with high concentrations of carbon dioxide. A microbial potential to reduce ferric iron was found in the sediments. In ML 111 and ML 117 the concentrations of Fe(II) in the epilimnion were markedly higher than in the oxic hypolimnetic layers. It can be suggested that the occurence of ferrous iron in the epilimnion is of photochemical origin, as described for softwater lakes. Minimum concentrations of dissolved organic carbon in the epilimnion could be correlated to the increase of ferrous iron concentrations. Especially in springtime and summer the concentrations of Fe(II) in the epilimnion were higher than in the oxic hypolimnetic layer below.  相似文献