Particulate material composition in the Lena River-Laptev Sea system: Scales of heterogeneities     

O. V. Dudarev  I. P. Semiletov  A. N. Charkin 《Doklady Earth Sciences》2006,411(2):1445-1451

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The development of high-viscous oil resources of petroleum fields     

V. V. Bulaev  S. N. Zakirov  E. S. Zakirov 《Doklady Earth Sciences》2006,407(2):349-351

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Classifying coastal waters: Current necessity and historical perspective     

J. C. Kurtz  N. D. Detenbeck  V. D. Engle  K. Ho  L. M. Smith  S. J. Jordan  D. Campbell 《Estuaries and Coasts》2006,29(1):107-123

Coastal ecosystems are ecologically and commercially valuable, productive habitats that are experiencing escalating compromises of their structural and functional integrity. The Clean Water Act (USC 1972) requires identification of impaired water bodies and determination of the causes of impairment. Classification simplifies these determinations, because estuaries within a class are more likely to respond similarly to particular stressors. We reviewed existing classification systems for their applicability to grouping coastal marine and Great Lakes water bodies based on their responses to aquatic stressors, including nutrients, toxic substances, suspended sediments, habitat alteration, and combinations of stressors. Classification research historically addressed terrestrial and freshwater habitats rather than coastal habitats. Few efforts focused on stressor response, although many well-researched classification frameworks provide information pertinent to stressor response. Early coastal classifications relied on physical and hydrological properties, including geomorphology, general circulation patterns, and salinity. More recent classifications sort ecosystems into a few broad types and may integrate physical and biological factors. Among current efforts are those designed for conservation of sensitive habitats based on ecological processes that support patterns of biological diversity. Physical factors, including freshwater inflow, residence time, and flushing rates, affect sensitivity to stressors. Biological factors, such as primary production, grazing rates, and mineral cycling, also need to be considered in classification. We evaluate each existing classification system with respect to objectives, defining factors, extent of spatial and temporal applicability, existing sources of data, and relevance to aquatic stressors. We also consider classification methods in a generic sense and discuss their strengths and weaknesses for our purposes. Although few existing classifications are based on responses to stressors, may well-researched paradigms provide important information for improving our capabilities for classification, as an investigative and predictive management tool.  相似文献   

Regional model assessments of fire risks under global climate changes     

I. I. Mokhov  A. V. Chernokulsky  I. M. Shkolnik 《Doklady Earth Sciences》2006,411(2):1485-1488

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Degree of thermal impact on the periphery of the Siberian craton in the Phanerozoic     

F. A. Letnikov  Yu. A. Kostitsyn  E. E. Krasil’nikova  E. I. Mishina 《Doklady Earth Sciences》2006,409(1):706-708

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Geochemical and isotopic features of basalts in the axial Mid-Atlantic Ridge near the Martin Vaz Fracture Zone, South Atlantic (19°–20° S)     

S. G. Skolotnev  A. A. Peive  B. V. Belyatskii 《Doklady Earth Sciences》2006,407(2):401-407

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Age of granitoids in the Man’khambo and Il’yaiz plutons, the northern Urals: U-Pb data     

O. V. Udoratina  A. A. Soboleva  N. A. Kuzenkov  N. V. Rodionov  S. L. Presnyakov 《Doklady Earth Sciences》2006,407(1):284-289

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Contamination of Silurian volcanic rocks in the Tagil synform by Precambrian zircon     

V. N. Puchkov  O. M. Rosen  D. Z. Zhuravlev  E. V. Bibikova 《Doklady Earth Sciences》2006,411(2):1381-1384

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Porphyroblast rotation during crenulation cleavage development: an example from the aureole of the Mooselookmeguntic pluton, Maine, USA   总被引：1，自引：0，他引：1  

S. E. JOHNSON  M. E. DUPEE  C. V. GUIDOTTI 《Journal of Metamorphic Geology》2006,24(1):55-73

In the low‐pressure, high‐temperature metamorphic rocks of western Maine, USA, staurolite porphyroblasts grew at c. 400 Ma, very late during the regional orogenesis. These porphyroblasts, which preserve straight inclusion trails with small thin‐section‐scale variation in pitch, were subsequently involved in the strain and metamorphic aureole of the c. 370 Ma Mooselookmeguntic pluton. The aureole shows a progressive fabric intensity gradient from effectively zero emplacement‐related deformation at the outer edge of the aureole ～2900 m (map distance) from the pluton margin to the development of a pervasive emplacement‐related foliation adjacent to the pluton. The development of this pervasive foliation spanned all stages of crenulation cleavage development, which are preserved at different distances from the pluton. The spread of inclusion‐trail pitches in the staurolite porphyroblasts, as measured in two‐dimensional (2‐D) thin sections, increases nonlinearly from ～16° to 75° with increasing strain in the aureole. These data provide clear evidence for rotation of the staurolite porphyroblasts relative to one another and to the developing crenulation cleavage. The data spread is qualitatively modelled for both pure and simple shear, and both solutions match the data reasonably well. The spread of inclusion‐trail orientations (40–75°) in the moderately to highly strained rocks is similar to the spread reported in several previous studies. We consider it likely that the sample‐scale spread in these previous studies is also the result of porphyroblast rotation relative to one another. However, the average inclusion‐trail orientation for a single sample may, in at least some instances, reflect the original orientation of the overgrown foliation.  相似文献   

Testing earthquake prediction methods: «The West Pacific short-term forecast of earthquakes with magnitude MwHRV ≥ 5.8»     

V.G. Kossobokov   《Tectonophysics》2006,413(1-2):25

Analyzing the tables and probability maps posted by Yan Y. Kagan and David D. Jackson in April 2002–September 2004 at http://scec.ess.ucla.edu/~ykagan/predictions_index.html and the catalog of earthquakes for the same period, the conclusion is drawn that the underlying method could be used for prediction of aftershocks, while it does not outscore random guessing when main shocks are considered.  相似文献