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31.
Otto Wilckens Wilckens Leuchs Rudolf Leutelt W. Salomon 《International Journal of Earth Sciences》1930,21(3):201-205
Ohne Zusammenfassung 相似文献
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Jutta ZIPFEL Bradley L. JOLLIFF Ralf GELLERT Kenneth E. HERKENHOFF Rudolf RIEDER Robert ANDERSON James F. BELL III Johannes BRÜCKNER Joy A. CRISP Philip R. CHRISTENSEN Benton C. CLARK Paulo A.
De SOUZA Jr. Gerlind DREIBUS Claude
D’USTON Thanasis ECONOMOU Steven P. GOREVAN Brian C. HAHN Göstar KLINGELHÖFER Timothy J. McCOY Harry Y. McSWEEN Jr. Douglas W. MING Richard V. MORRIS Daniel S. RODIONOV Steven W. SQUYRES Heinrich WÄNKE Shawn P. WRIGHT Michael B. WYATT Albert S. YEN 《Meteoritics & planetary science》2011,46(1):1-20
Abstract– The Opportunity rover of the Mars Exploration Rover mission encountered an isolated rock fragment with textural, mineralogical, and chemical properties similar to basaltic shergottites. This finding was confirmed by all rover instruments, and a comprehensive study of these results is reported here. Spectra from the miniature thermal emission spectrometer and the Panoramic Camera reveal a pyroxene‐rich mineralogy, which is also evident in Mössbauer spectra and in normative mineralogy derived from bulk chemistry measured by the alpha particle X‐ray spectrometer. The correspondence of Bounce Rock’s chemical composition with the composition of certain basaltic shergottites, especially Elephant Moraine (EET) 79001 lithology B and Queen Alexandra Range (QUE) 94201, is very close, with only Cl, Fe, and Ti exhibiting deviations. Chemical analyses further demonstrate characteristics typical of Mars such as the Fe/Mn ratio and P concentrations. Possible shock features support the idea that Bounce Rock was ejected from an impact crater, most likely in the Meridiani Planum region. Bopolu crater, 19.3 km in diameter, located 75 km to the southwest could be the source crater. To date, no other rocks of this composition have been encountered by any of the rovers on Mars. The finding of Bounce Rock by the Opportunity rover provides further direct evidence for an origin of basaltic shergottite meteorites from Mars. 相似文献
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Rudolf Stockar 《Swiss Journal of Geoscience》2010,103(1):101-119
The Ladinian Cassina beds belong to the fossiliferous levels of the world-famous Middle Triassic Monte San Giorgio Lagerstätte (UNESCO World Heritage List, Canton Ticino, Southern Alps). Although they are a rich archive for the depositional environment of an important thanatocoenosis, previous excavations focused on vertebrates and particularly on marine reptiles. In 2006, the Museo Cantonale di Storia Naturale (Lugano) started a new research project focusing for the first time on microfacies, micropalaeontological, palaeoecological and taphonomic analyses. So far, the upper third of the sequence has been excavated on a surface of around 40 m2, and these new data complete those derived from new vertebrate finds (mainly fishes belonging to Saurichthys, Archaeosemionotus, Eosemionotus and Peltopleurus), allowing a better characterization of the basin. Background sedimentation on an anoxic to episodically suboxic seafloor resulted in a finely laminated succession of black shales and limestones, bearing a quasi-anaerobic biofacies, which is characterized by a monotypic benthic foraminiferal meiofauna and has been documented for the first time from the whole Monte San Giorgio sequence. Event deposition, testified by turbidites and volcaniclastic layers, is related to sediment input from basin margins and to distant volcanic eruptions, respectively. Fossil nekton points to an environment with only limited connection to the open sea. Terrestrial macroflora remains document the presence of emerged areas covered with vegetation and probably located relatively far away. Proliferation of benthic microbial mats is inferred on the basis of microfabrics, ecological considerations and taphonomic (both biostratinomic and diagenetic) features of the new vertebrate finds, whose excellent preservation is ascribed to sealing by biofilms. The occurrence of allochthonous elements allows an insight into the shallow-waters of the adjoining time-equivalent Salvatore platform. Finally, the available biostratigraphic data are critically reviewed. 相似文献
36.
Rudolf V. Zhang 《寒旱区科学》2014,6(4):0348-0355
Global climate warming which began in the second half of the twentieth century is continuing. It is associated with increased risks for ecological management, especially in permafrost areas comprising over 65% of Russia. Of special concern are dams constructed on permafrost. They are subject not only to climatic impacts, but also to additional hydrothermal loads from water reservoirs. This paper presents the concept of geocryological monitoring of dams and other water resource projects and substantiates its necessity in view of climatic change. It also presents methods, scope and implementation of geocryological monitoring at medium and small dams, considering the specific nature of Far Northern areas, as well as the complicated geotechnical, hydrogeological and permafrost conditions. 相似文献
37.
Rudolf V. Zhang 《寒旱区科学》2014,6(4):0340-0347
This article discusses the current concepts of dam design and construction in permafrost regions. It is demonstrated that embankment dams often change their state from frozen to thawed and back during the operation period. It is shown that these transitions are not always attributable to observed climate warming. Where geotechnical, hydrogeological, and permafrost conditions are complicated, proper performance of embankment dams can only be provided by adhering to a selected thermal design for, as an example, a frozen state. 相似文献
38.
Kaelin M. Cawley Youhei Yamashita Nagamitsu Maie Rudolf Jaffé 《Estuaries and Coasts》2014,37(2):399-410
Dissolved organic carbon (DOC) concentration and dissolved organic matter (DOM) optical properties were analyzed along two estuarine river transects during the wet and dry seasons to better understand DOM dynamics and quantify mangrove inputs. A tidal study was performed to assess the impacts of tidal pumping on DOM transport. DOM in the estuaries showed non-conservative mixing indicative of mangrove-derived inputs. Similarly, fluorescence data suggest that some terrestrial humic-like components showed non-conservative behavior. An Everglades freshwater-derived fluorescent component, which is associated with soil inputs from the Northern Everglades, behaved conservatively. During the dry season, a protein-like component behaved conservatively until the mid-salinity range when non-conservative behavior due to degradation and/or loss was observed. The tidal study data suggests mangrove porewater inputs to the rivers following low tide. The differences in quantity of DOM exported by the Shark and Harney Rivers imply that geomorphology and tidal hydrology may be a dominant factor controlling the amount of DOM exported from the mangrove ecotone, where up to 21 % of the DOC is mangrove-derived. Additionally, nutrient concentrations and other temporal factors may control DOM export from the mangroves, particularly for the microbially derived fluorescent components, contributing to the seasonal differences. The wet and dry season fluxes of mangrove DOM from the Shark River is estimated as 0.27?×?109 mg C d?1 and 0.075?×?109 mg C d?1, respectively, and the Harney River is estimated as 1.9?×?109 mg C d?1 and 0.20?×?109 mg C d?1. 相似文献
39.
A new mimic biological Semi-permeable Membrane Device (SPMD) introduced for sampling organic pollutants yielded satisfactory results when it was frrst used as a passive sampler to concentrate and determine 16 kinds of polynuclear aromatic hydrocarbons (PAHs) by means of capillary GC on an HP 5890 GC-FID in coastal sediment perewater. The concentration of PAHs in sediment porewater for naphthalene(N), acenaphthlene(AL), acenaphthene (AE), fluorene (F), phenaphthene(P), anthracene(A), fluoranthene(FA), pyrene(Py), benzo[a]anthracene(B[a]A), chrysene(Chr), benzo[b] fluor- anthene(B[b]F), benzo[k]fluoranthene(B[k]F), benzo[a]pyrene(B[a]P),indeno[1,2,3,-cd]-Pyrene(I[123]P), dibenz[a,h]anthracene(D[ab]A) and benzo[g,h,i] perylene(B[ghi]P) were:50.36, under detection limits(UD), 18.19, 8.41, 8.40, 1.44, UD, 8.01, 524.15, 168.47, 50.13,123.66, 63.48, 27.40, 82.04 and 58,81 ng/L, respectively. 相似文献
40.
Matched-field tracking (MFT) algorithms have been successfully applied to both simulated and measured data to determine the most likely positions of a sound source that is localized ambiguously by a matched-field processing (MFP) system. They have been used to track sources moving linearly or on a circular path at constant speed and heading. The input to the trackers is a set of ambiguity surfaces, contiguous in time, generated by MFP. These algorithms assume that the track start and end times are known a priori; this restriction is removed in the piecewise MFT algorithm (PTA). The PTA was applied to narrow-band measured data collected during the PACIFIC SHELF 93 trial to successfully identify the significant source track segments 相似文献