Implications of a ductile crustal layer for the deformation caused by the Fennoscandian ice sheet     

Volker Klemann  & Detlef Wolf  《Geophysical Journal International》1999,139(1):216-226

  相似文献   

Effects of lateral viscosity variations on postglacial rebound: an analytical approach     

Georg Kaufmann  & Detlef Wolf 《Geophysical Journal International》1999,137(2):489-500

  相似文献   

Gravitational viscoelastic relaxation of eccentrically nested spheres     

Zdenk Martinec  & Detlef Wolf 《Geophysical Journal International》1999,138(1):45-66

We present a semi-analytical solution to the 2-D forward modelling of viscoelastic relaxation in a heterogeneous model consisting of eccentrically nested spheres. Several numerical methods for 2-D and 3-D viscoelastic relaxation modelling have been applied recently, including finite-element and spectral-finite-difference schemes. The present semi-analytical approach provides a model response against which more general numerical algorithms can be validated. The eccentrically nested sphere solution has been tested by comparing it with the analytical solutions for viscoelastic relaxation in a homogeneous sphere and in two concentrically nested spheres, and good agreement was obtained.  相似文献   

Viscoelastic perturbations of the earth: significance of the incremental gravitational force in models of glacial isostasy     

Falk Amelung  Detlef Wolf 《Geophysical Journal International》1994,117(3):864-879

  相似文献   

Korrektur zur Arbeit „Experimentelle Untersuchung der Metamorphose von kieselig dolomitischen Sedimenten     

Priv.-Doz. Dr. Paul Metz  Dr. Detlef Puhan 《Contributions to Mineralogy and Petrology》1971,31(2):169-170

Ohne Zusammenfassung  相似文献   

Seasonal and interannual variability of the planktic foraminiferal flux in the vicinity of the Azores Current     

David Storz  Hartmut Schulz  Joanna J. Waniek  Detlef E. Schulz-Bull  Michal Kučera 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(1):107-124

Planktic foraminiferal (PF) flux and faunal composition from three sediment trap time series of 2002–2004 in the northeastern Atlantic show pronounced year-to-year variations despite similar sea surface temperature (SST). The averaged fauna of the in 2002/2003 is dominated by the species Globigerinita glutinata, whereas in 2003/2004 the averaged fauna is dominated by Globigerinoides ruber. We show that PF species respond primarily to productivity, triggered by the seasonal dynamics of vertical stratification of the upper water column. Multivariate statistical analysis reveals three distinct species groups, linked to bulk particle flux, to chlorophyll concentrations and to summer/fall oligotrophy with high SST and stratification. We speculate that the distinct nutrition strategies of strictly asymbiontic, facultatively symbiontic, and symbiontic species may play a key role in explaining their abundances and temporal succession. Advection of water masses within the Azores Current and species expatriation result in a highly diverse PF assemblage. The Azores Frontal Zone may have influenced the trap site in 2002, indicated by subsurface water cooling, by highest PF flux and high flux of the deep-dwelling species Globorotalia scitula. Similarity analyses with core top samples from the global ocean including 746 sites from the Atlantic suggest that the trap faunas have only poor analogs in the surface sediments. These differences have to be taken into account when estimating past oceanic properties from sediment PF data in the eastern subtropical North Atlantic.  相似文献   

Erratum to “Evidence of estuarine nursery origin of five coastal fish species along the Portuguese coast through otolith elemental fingerprints” [Estuar. Coast. Shelf Sci. 79 (2008) 317–327]     

Rita P. Vasconcelos  Patrick Reis-Santos  Susanne Tanner  Anabela Maia  Christopher Latkoczy  Detlef Günther  Maria José Costa  Henrique Cabral 《Estuarine, Coastal and Shelf Science》2009

  相似文献   

A cornucopia of presolar and early solar system materials at the micrometer size range in primitive chondrite matrix     

Philip A. Bland  Frank J. Stadermann  Christine Floss  Detlef Rost  Edward P. Vicenzi  Anton T. Kearsley  Gretchen K. Benedix 《Meteoritics & planetary science》2007,42(7-8):1417-1427

Abstract— We have used a variety of complementary microanalytical techniques to constrain the mineralogy, trace‐element distributions, and oxygen‐isotopic compositions in a 50 × 50 μm area of Acfer 094 matrix. The results reveal the exceptional mineralogical and compositional heterogeneity of this material at the sub‐μm level. We observe μm‐scale and sub‐μm grains with elemental associations suggesting feldspar, metal with widely varying Ni contents, and a Cr‐Fe alloy (in addition to forsterite, pyroxene, sulfide, ferrihydrite, and amorphous groundmass previously described). A new class of μm‐scale CAI (μCAI) is also observed, which show sub‐μm compositional zoning, and a range of oxygen isotopic compositions. Unlike the larger CAIs in Acfer 094, which are uniformly ¹⁶O‐enriched, two of the three μCAIs we analyzed are isotopically normal. We also observed a Li‐rich hotspot that detailed analysis by ToF‐SIMS suggests may be a LiCr‐oxide grain. Within the resolution of the NanoSIMS, this grain has isotopically normal Li. Finally, in our 50 × 50 μm area, we positively identified a presolar grain that is the most ¹⁸O‐rich silicate found so far in meteorites. The grain may originate from an asymptotic giant branch (AGB) star, or more likely, a supernova. In line with previous TEM studies (Greshake 1997), we find no evidence for clastic material (e.g., fragmental chondrules) in the matrix of Acfer 094: although the matrix is volatile‐depleted, this depletion does not appear to result from dilution of a primordial starting material with (depleted) chondrule fragments. Assuming that matrix experienced the depletion event, our data on the detailed mineralogy of Acfer 094 are currently equivocal in constraining the nature of that event. We observe carrier phases for several elements consistent with conditions approaching equilibrium condensation; however, the presence of an amorphous groundmass is suggestive of more rapid cooling.  相似文献   

The implications of climate policy for the impacts of climate change on global water resources   总被引：1，自引：0，他引：1  

Nigel W. Arnell  Detlef P. van VuurenMorna Isaac 《Global Environmental Change》2011,21(2):592-603

This paper assesses the implications of climate policy for exposure to water resources stresses. It compares a Reference scenario which leads to an increase in global mean temperature of 4 °C by the end of the 21st century with a Mitigation scenario which stabilises greenhouse gas concentrations at around 450 ppm CO₂e and leads to a 2 °C increase in 2100. Associated changes in river runoff are simulated using a global hydrological model, for four spatial patterns of change in temperature and rainfall. There is a considerable difference in hydrological change between these four patterns, but the percentages of change avoided at the global scale are relatively robust. By the 2050s, the Mitigation scenario typically avoids between 16 and 30% of the change in runoff under the Reference scenario, and by 2100 it avoids between 43 and 65%. Two different measures of exposure to water resources stress are calculated, based on resources per capita and the ratio of withdrawals to resources. Using the first measure, the Mitigation scenario avoids 8-17% of the impact in 2050 and 20-31% in 2100; with the second measure, the avoided impacts are 5-21% and 15-47% respectively. However, at the same time, the Mitigation scenario also reduces the positive impacts of climate change on water scarcity in other areas. The absolute numbers and locations of people affected by climate change and climate policy vary considerably between the four climate model patterns.  相似文献   

Global and regional evolution of short-lived radiatively-active gases and aerosols in the Representative Concentration Pathways   总被引：3，自引：0，他引：3  

Jean-Fran?ois Lamarque  G. Page Kyle  Malte Meinshausen  Keywan Riahi  Steven J. Smith  Detlef P. van Vuuren  Andrew J. Conley  Francis Vitt 《Climatic change》2011,109(1-2):191-212

In this paper, we discuss the results of 2000?C2100 simulations following the emissions associated with the Representative Concentration Pathways (RCPs) with a chemistry-climate model, focusing on the changes in 1) atmospheric composition (troposphere and stratosphere) and 2) associated environmental parameters (such as nitrogen deposition). In particular, we find that tropospheric ozone is projected to decrease (RCP2.6, RCP4.5 and RCP6) or increase (RCP8.5) between 2000 and 2100, with variations in methane a strong contributor to this spread. The associated tropospheric ozone global radiative forcing is shown to be in agreement with the estimate used in the RCPs, except for RCP8.5. Surface ozone in 2100 is projected to change little compared from its 2000 distribution, a much-reduced impact from previous projections based on the A2 high-emission scenario. In addition, globally-averaged stratospheric ozone is projected to recover at or beyond pre-1980 levels. Anthropogenic aerosols are projected to strongly decrease in the 21st century, a reflection of their projected decrease in emissions. Consequently, sulfate deposition is projected to strongly decrease. However, nitrogen deposition is projected to increase over certain regions because of the projected increase in NH₃ emissions.  相似文献