The Far‐Infrared Emission of Galaxies     

Carsten Kramer  Albrecht Poglitsch  Jürgen Stutzki  Andreas Eckart 《Astronomische Nachrichten》2005,326(7):523-534

C01 Study of local infrared bright galaxies with HERSHCEL‐PACS C02 PDR modeling of the COBE Far‐Infrared data of the Milky Way C03 MAMBO observations of BzK‐selected vigorous starburst galaxies at z ∼ 2 C04 Starburst galaxies in the far‐infrared. Modelling the line, PAH and dust continuum emission C05 The SED from isothermal clouds C06 PDRs in M83 and M51: The road to HIFI/Herschel and SOFIA C07 Large Scale Mapping of Molecular Gas in the Vicinity of 30 Doradus in the Large Magellanic Cloud C08 Modelling far‐infrared emission from dust in gas‐rich galaxies C09 [CII]/CO(1‐0) Line Ratio at low Metallicities C10 Gas, Stars and Dust in the Spiral Arms of M51 C11 The ISOPHOT 170 micron Serendipity Survey (ISOSS) catalog of optically identified galaxies C12 Spitzer Images of M33: A Probe to Radio‐FIR Correlation C13 Observations of far‐infrared emission from dust in gas‐rich galaxies C14 Dust and Gas in Nearby Galaxies: First Results from SINGS and THINGS C15 Sequential Starburst in Arp220?  相似文献   

Fusulinids and stratigraphy of the Carboniferous and Permian in Iran     

E. Ja. Leven  M. N. Gorgij 《Stratigraphy and Geological Correlation》2011,19(7):687-776

  相似文献   

Submicromolar Oxygen Profiles at the Oxic–Anoxic Boundary of Temperate Lakes     

Mathias K. Kirf  Christian Dinkel  Carsten J. Schubert  Bernhard Wehrli 《Aquatic Geochemistry》2014,20(1):39-57

Elements involved in biogeochemical cycles undergo rapid turnover at the oxic–anoxic interface of stratified lakes. Here, the presence or absence of oxygen governs abiotic and biotic processes and rates. However, achieving a detailed sampling resolution to precisely locate the oxic–anoxic interface is difficult due to a lack of fast, drift-free sensors in the working range of 10 to a few 1,000 nmol O₂ L^?1. Here, we demonstrate that conventional amperometric and optical microsensors can be used to resolve submicromolar oxygen concentrations in a continuous profiling mode. The amperometric drift was drastically reduced by anoxic preconditioning. In situ offset correction in the anoxic layer and a high amplification scheme allowed for an excellent detection limit of < 10 nmol L^?1. The optical microsensors also showed a similar performance with a detection limit of < 20 nmol L^?1. Their drift stability allowed for a laboratory calibration in combination with a minor in situ anoxic offset correction. The two different sensor systems showed virtually identical profiles during parallel use in stratified lakes. Both sensors were able to resolve the fine-scale structure at the oxic–anoxic interface and revealed hitherto unnoticed extended zones of submicromolar oxygen concentrations even below a steep oxycline. The zones extended up to several meters and showed substantial vertical variability. These results underline the need of a precise localization of the oxic–anoxic interface on a submicromolar scale in order to constrain the relevant aerobic and anaerobic redox processes.  相似文献   

Lower Permian formations of different geodynamic environments in A'nyemaqen ophiolitic zone (Buqingshan Mts., eastern Kunlun, Qinghai Province, China)     

I.I.Pospelov  E.Ya.Leven  O.A.Korchagin 《东北亚地学研究》2005,(Z1)

Lower Permian formations within the Buqingshan Mountains (A'nyemaqen ophiolitic zone, eastern sector of the eastern Kunlun) were formed in the following paleogeodynamic environments (from north to south): (1) shelf and slope of a passive continental margin in a marginal sea; (2) partially Permian metamorphic rocks of subduclion-accretion complexes and volcanogenic rocks of an ensimatic island arc, of the age limited from above by the Asselian - Sakmarian; and (3 ) an island arc slope and oceanic trench. Subduction-accretion complexes and the island arc volcanites are overlain with a sharp angular unconformity by a carbonate-conglomerate sequence, which presents as local molasse of the Early Permian age. Based on fusulinids from the basal limestone, the age of the local molasse is first defined as the Yakhtashian-Bolorian, i.e. Artinskian-Kungurian (?). The thorough investigations revealed that the initial closure of the eastern Paleotethys within the eastern Kunlun corresponded to the Sakmarian-Yakhtashian (Artinskian) boundary, whereas in the western Paleotethys sector (Northern Pamirs) the closure occurred considerably earlier, prior to the Late Bashkirian. Thus, the idea that the Paleotethys in the eastern Kunlun reached its maximum width in the Permian, is highly questionable. During the Early Permian the A'nyemaqen branch of the Paleotethys intensely decreased. Beginning from the Bolorian (Kungurian) and up to the end of the Permian this branch represented its relict in the form of a marginal sea depression. It may be suggested that the Paleotethys closure in the A'nyemaqen took place gradually from the west to the east and covered a long period from the Late Carboniferous to the terminal Early Permian.  相似文献   

Magnetic anomalies and rock magnetism of basalts from Reykjanes (SW-Iceland)     

Frank Dietze  Agnes Kontny  Ingo Heyde  Carsten Vahle 《Studia Geophysica et Geodaetica》2011,55(1):109-130

This study presents rock magnetic properties along with magnetic field measurements of different stratigraphic and lithologic basalt units from Reykjanes, the southwestern promontory of the Reykjanes peninsula, where the submarine Reykjanes Ridge passes over into the rift zone of southwestern Iceland. The basaltic fissure eruptions and shield lava of tholeiitic composition (less than 11500 a old) show a high natural remanent magnetization (NRM, J_r) up to 33.6 A/m and high Koenigsberger ratio (Q) up to 52.2 indicating a clear dominance of the NRM compared to the induced part of the magnetization. Pillow basalts and picritic shield lava show distinctly lower J_r values below 10 A/m. Magnetic susceptibility (κ) ranges for all lithologies from 2.5 to 26×10⁻³ SI.  相似文献   

Mechanisms of Archean crust formation inferred from high-precision HFSE systematics in TTGs   总被引：7，自引：0，他引：7  

J. Elis Hoffmann  Carsten Münker  Minik T. Rosing  Dieter Garbe-Schönberg 《Geochimica et cosmochimica acta》2011,75(15):4157-6628

It has been proposed that Archean tonalitic-trondhjemitic-granodioritic magmas (TTGs) formed by melting of mafic crust at high pressures. The residual mineralogy of the TTGs (either (garnet)-amphibolite or rutile-bearing eclogite) is believed to control the trace element budget of TTGs. In particular, ratios of high-field-strength elements (HFSE) can help to discriminate between the different residual lithologies. In order to place constraints on the source mineralogy of TTGs, we performed high-precision HFSE measurements by isotope dilution (Nb, Ta, Zr, Hf) together with Lu-Hf and Sm-Nd measurements on representative, ca. 3.85-2.8 Ga TTGs and related rock types from southern West Greenland, W-India and from the Superior Province. These measurements are complemented by major and trace element data for the TTGs. Texturally homogeneous early Archean (3.85-3.60 Ga old) and Mesoarchean (ca. 3.1-2.8 Ga old) TTGs have both low Ni (<11 ppm) and Cr contents (<20 ppm), indicating that there was little or no interaction with mantle peridotite during ascent. Ratios of Nb/Ta in juvenile Eoarchean TTGs range from ca. 7 to ca. 24, and in juvenile Mesoarchean TTGs from ca. 14 to ca. 27. Even higher Nb/Ta (14-42) were obtained for migmatitic TTGs and intra-crustal differentiates, most likely mirroring further fractionation of Nb from Ta as a consequence of partial melting, fluid infiltration and migmatisation. In the juvenile TTGs, positive correlations between Nb/Ta and Gd/Yb, La/Yb, Sr/Y, Zr/Sm and Zr/Nb are observed. These compositional arrays are best explained by melting of typical Isua tholeiites in both, the rutile-bearing eclogite stability field (>15 kbar, high Nb/Ta) and the garnet-amphibolite stability field (10-15 kbar, low Nb/Ta). With respect to the low end of Nb/Ta found for TTGs, there is currently some uncertainty between the available experimental datasets for amphibole. Independent of these uncertainties, the TTG compositions found here still require the presence of both endmember residues. A successful geological model for the TTGs therefore has to account for the co-occurrence of both low- and high-Nb/Ta TTGs within the same geologic terrane. An additional feature observed in the Eoarchean samples from Greenland is a systematic co-variation between Nb/Ta and initial εHf(t), which is best explained by a model where TTG-melting occured at progressively increasing pressures in a pile of tectonically thickened mafic crust. The elevated Nb/Ta in migmatitic TTGs and intra-crustal differentiates can shed further light on the role of intra-crustal differentiation processes in the global Nb/Ta cycle. Lower crustal melting processes at granulite facies conditions may generate high-Nb/Ta domains in the middle crust, whereas mid-crustal melting at amphibolite facies conditions may account for the low Nb/Ta generally observed in upper crustal rocks.  相似文献   

The first findings of fusulinids in the sections of the Sabzevar tectonic block (Iran)     

M. N. Gorgij  E. Ja. Leven 《Stratigraphy and Geological Correlation》2013,21(1):8-17

The first fusulinids have been recorded from the eastern part of the Sabzevar tectonic block (Kuh-e-Ahuban Mountains, to the north of the town of Kashmar). The fusulinids have been grouped into two complexes. The first complex is represented by several species of the genus Rauserites, of probable Gzhelian age. The second complex is represented by numerous representatives of the Asselian genera Sphaeroschwagerina and Pseudoschwagerina, as well as species of the genera Schubertella, Rugosofusulina, Rugosochusenella and Praepseudofusulina. The age of these complexes is similar to that of complexes previously described from sections of Anarak (the Yazd block) and Zaladou (the Tabas block), but differ in the species composition. Many of the species present in these complexes are similar or identical to species from standard sections of Gzhelian and Asselian Stages of the Moskovian syncline and the Urals, which indicates that there were free connections between the East European and Iranian basins in Gzhelian and Asselian Stages.  相似文献   

Natural hazards and resilience: exploring institutional and organizational dimensions of social resilience   总被引：1，自引：1，他引：0  

Gérard Hutter  Christian Kuhlicke  Thomas Glade  Carsten Felgentreff 《Natural Hazards》2013,67(1):1-6

  相似文献   

A laboratory study of tracer tomography     

R. Brauchler  G. Böhm  C. Leven  P. Dietrich  M. Sauter 《Hydrogeology Journal》2013,21(6):1265-1274

A tracer tomographic laboratory study was performed with consolidated fractured rock in three-dimensional space. The investigated fractured sandstone sample was characterized by significant matrix permeability. The laboratory transport experiments were conducted using gas-flow and gas-tracer transport techniques that enable the generation of various flow-field patterns via adjustable boundary conditions within a short experimental time period. In total, 72 gas-tracer (helium) tests were performed by systematically changing the injection and monitoring configuration after each test. For the inversion of the tracer breakthrough curves an inversion scheme was applied, based on the transformation of the governing transport equation into a form of the eikonal equation. The reliability of the inversion results was assessed with singular value decomposition of the trajectory density matrix. The applied inversion technique allowed for the three-dimensional reconstruction of the interstitial velocity with a high resolution. The three-dimensional interstitial velocity distribution shows clearly that the transport is dominated by the matrix while the fractures show no apparent influence on the transport responses.  相似文献   

Delineating subsurface heterogeneity at a loop of River Steinlach using geophysical and hydrogeological methods   总被引：1，自引：1，他引：0  

Kennedy O. Doro  Carsten Leven  Olaf A. Cirpka 《Environmental Earth Sciences》2013,69(2):335-348

Stratigraphic heterogeneity is a key controlling factor for flow and transport in groundwater systems. In this case study, we have combined two- and three-dimensional images of electric resistivity with hydrogeological data to delineate such stratigraphic heterogeneity at a loop of River Steinlach close to Tübingen, Germany, where we estimated spatially varying aquifer parameters using established evaluation techniques. We developed a three-layer stratigraphic model consisting of heterogeneous sandy gravel overlain by a fine alluvium including top soil, and underlain by sandstone weathered at its top. The sandy gravel makes up the aquifer unit while we interpret the sandstone as aquitard. We classified the area into two stratigraphic segments based on resistivity data. The Southern segment consists of a thicker alluvium where the aquifer material contains more clay than in the Northern segment. Two different stratigraphic structures were also delineated at the Southern and Northern segments, respectively. These structures are visible in inversion results as low-resistivity features trending in the SE–NW in the Southern segment and NE–NW in the Northern segment. Both structures may be previous flow paths of River Steinlach, and the low permeability material overlying them may impair flow exchange in the area. We performed slug and pumping tests to estimate the hydraulic conductivity (K) of the aquifer. The K distributions show slight variation with higher values obtained at wells within the Northern segment and close to the river bank. A qualitative comparison of measured hydraulic conductivities with the resistivity distribution shows good agreement of the spatial patterns. The stratigraphic and hydraulic heterogeneities delineated in this work are important for experimental and modeling studies of flow, transport, and hyporheic exchange at the site.  相似文献