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321.
Gerald Pischinger Walter Kurz Martin Übleis Magdalena Egger Harald Fritz Franz Josef Brosch Karl Stingl 《Swiss Journal of Geoscience》2008,101(1):235-254
The Paleogene and Neogene evolution of Austroalpine basement units east of the Tauern Window is characterised by the formation of two major sets of faults: (1) ESE–WNW- to E–W-trending faults, associated with ENE- and NNW-trending conjugate structures and (2) N–S to NNE-SSW striking structures, mainly acting as high-angle normal faults, often associated with E-dipping low-angle normal faults along the western margin of the Styrian Basin.Together with the stratigraphic evolution of the Styrian and Lavanttal Basins and the related subsidence histories a tectonic evolution may be reconstructed for this part of the Eastern Alps. In the southern part of the Koralm Massif, WNW-trending fractures were activated as dextral strike-slip faults, associated with the evolution of WNW-trending troughs filled up with coarse block debris. W- to WNW-trending fractures were reactivated as normal faults, indicating N–S extension. It is assumed that these phases resulted in subsidence and block debris sedimentation in Karpatian and Badenian times (ca. 17–13 Ma).In the Western Styrian Basin no Sarmatian (13–11.5 Ma) sediments are observed; Pannonian (11.5 to 7.1 Ma) sediments are restricted to the Eastern Styrian Basin. This indicates, that the Koralm basement and the Western Styrian Basin were affected by post-Sarmatian uplift, coinciding with a re-activation of N-trending normal faults along the eastern margin of the Koralm Massif. Therefore, we suggest that the final uplift of the Koralm Complex, partly together with the Western Styrian Basin, occurred during the early Pannonian (at approximately 10 Ma). The elevation of clastic deposits indicates that the Koralm Complex was elevated by approximately 800 m during this phase, associated with an additional phase of E–W-directed extension accommodated by N–S striking normal faults. 相似文献
322.
Matthias Kokorsch Karl Benediktsson 《Norsk geografisk tidsskrift. Norwegian journal of geography》2018,72(2):97-114
The concept of resilience has been used to assess community development and its prospects in natural resource-based localities. The objectives of the article are to evaluate the resilience of two Icelandic coastal communities, and to reflect on the possible shortcomings of the resilience concept for providing policy guidance. Mixed qualitative methods were used, with several weeks of fieldwork in each location. The results showed that the two case communities have had to adjust to a radical change in the fisheries management, with the loss of resource entitlements. Additionally, substantial differences were found in their level of resilience. One community was undergoing a transition towards a non-fisheries-based existence through several innovative new initiatives, while the other was struggling to adjust and seemed to have reached its limits of resilience, as witnessed by continuing outmigration and declining services. A state-sponsored programme to rekindle the local economy has had limited success so far. The authors conclude by identifying some of the limitations of the focus on endogenous strategies in much of the resilience literature, which does not pay much attention to the broader political economy. 相似文献
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Despite advances in cartography, mapping is still a costly process which involves a substantial amount of manual work. This article presents a method for automatically deriving road attributes by analyzing and mining movement trajectories (e.g. GPS tracks). We have investigated the automatic extraction of eight road attributes: directionality, speed limit, number of lanes, access, average speed, congestion, importance, and geometric offset; and we have developed a supervised classification method (decision tree) to infer them. The extraction of most of these attributes has not been investigated previously. We have implemented our method in a software prototype and we automatically update the OpenStreetMap (OSM) dataset of the Netherlands, increasing its level of completeness. The validation of the classification shows variable levels of accuracy, e.g. whether a road is a one‐ or a two‐way road is classified with an accuracy of 99%, and the accuracy for the speed limit is 69%. When taking into account speed limits that are one step away (e.g. 60 km/h instead of the classified 50 km/h) the classification increases to 95%, which might be acceptable in some use‐cases. We mitigate this with a hierarchical code list of attributes. 相似文献
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Climate change with respect to summer temperature throughout the Holocene is inferred from oscillations in the local Pinus sylvestris, Alnus incana and Betula pubescens forest‐lines, as recorded by fossil pollen and plant macrofossils in lake sediments at four altitudinal levels. Mt Skrubben (848 m a.s.l.), in Dividalen, was deglaciated down to below 280 m a.s.l. during 10 800–10 300 cal. yr BP. Betula pubescens established 10100 cal. yr BP at 280 m a.s.l. and expanded up to near the summit during the next 700 years. Birch woodland prevailed on the mountain plateau until 3300 cal. yr BP. Local Pinus sylvestris stands are recorded up to 400 m a.s.l. at 8450 cal. yr BP and >548 m a.s.l. about 8160 cal. yr BP. Alnus incana expanded from 400 to nearly 790 m a.s.l. during the period 7900–7600 cal. yr BP. The maximum forest distribution lasted until ca. 6000 cal. yr BP. Marked climatic deteriorations caused lowering of the forest‐lines around 4600 and 3000 cal. yr BP. Reconstruction of the summer temperature indicated mean July temperatures at 400 m a.s.l. of 1.5–3°C above the present during the period of maximum forest expansion, whereas >3°C above the present temperature at 548 m a.s.l. This is in accordance with other regional temperature reconstructions from northern Europe. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Amino acids, neutral sugars and amino sugars were analyzed to investigate the chemical composition and diagenetic processing of suspended particulate organic matter (POM, > 100 nm), high-molecular-weight dissolved organic matter (HMW DOM, 1–100 nm) and low-molecular-weight dissolved organic matter (LMW DOM, < 1 nm) at the time-series stations near Bermuda (BATS) and Hawaii (HOT). Differences between BATS and HOT were principally related to location-specific biogeochemical processes and water mass ventilation ages. Concentrations of amino acids, neutral sugar and amino sugars in unfiltered seawater sharply declined with depth at both stations, indicating an upper ocean source and rapid turnover of these components. The size distribution of organic matter was heavily skewed to smaller molecular sizes. Depth comparisons showed that larger size classes of organic matter were more efficiently removed than smaller size classes. Carbon-normalized yields of amino acids, neutral sugars and amino sugars decreased rapidly with depth and molecular size. Together these biochemicals accounted for 55% of organic carbon in surface POM but only 2% of the organic carbon in LMW DOM in deep water. Chemical compositions showed distinct differences between organic matter size classes indicating the extent of diagenetic processing increased with decreasing molecular size. These findings are consistent with the size-reactivity continuum model for organic matter in which bioreactivity decreases with decreasing molecular size and diagenetic processes lead to the formation of smaller components that are resistant to biodegradation. The data also provided evidence for a size-composition continuum. Carbon-normalized yields of amino acids, neutral sugars and amino sugars were sensitive indicators of diagenetic alterations. Diagenetic indicators based on amino acid compositions revealed distinct patterns for the North Pacific and Sargasso Sea possibly indicating the influence of varying sources or diagenetic processing. 相似文献