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991.
Craig E. Colten 《Geographical review》2019,109(3):416-435
Adaptation is a key concept in long‐term human adjustments to climate change. Despite the centrality of human decisions and actions in adaptation, much of the climate change literature is thin on humanities and social science which are the primary approaches for understanding human activity. This situation is particularly pronounced in Louisiana's discussions about its disappearing coast line where research has concentrated in understanding biophysical processes and solutions prioritize short‐term adaptations. This paper reviews the relationship of adaptation and long‐term transitions in the global change discussion and traces how disjointed adaptations in coastal Louisiana have contributed to a perilous environmental situation there. It proposes a shift from discrete adaptations to efforts that incorporate interrelated biophysical and human adaptations that can sustain long‐term transitions. 相似文献
992.
Michael J. Steventon Christopher A.‐L. Jackson David M. Hodgson Howard D. Johnson 《Basin Research》2019,31(3):600-620
Strain style, magnitude and distribution within mass‐transport complexes (MTCs) are important for understanding the process evolution of submarine mass flows and for estimating their runout distances. Structural restoration and quantification of strain in gravitationally driven passive margins have been shown to approximately balance between updip extensional and downdip contractional domains; such an exercise has not yet been attempted for MTCs. We here interpret and structurally restore a shallowly buried (c. 1,500 mbsf) and well‐imaged MTC, offshore Uruguay using a high‐resolution (12.5 m vertical and 15 × 12.5 m horizontal resolution) three‐dimensional seismic‐reflection survey. This allows us to characterise and quantify vertical and lateral strain distribution within the deposit. Detailed seismic mapping and attribute analysis shows that the MTC is characterised by a complicated array of kinematic indicators, which vary spatially in style and concentration. Seismic‐attribute extractions reveal several previously undocumented fabrics preserved in the MTC, including internal shearing in the form of sub‐orthogonal shear zones, and fold‐thrust systems within the basal shear zone beneath rafted‐blocks. These features suggest multiple transport directions and phases of flow during emplacement. The MTC is characterised by a broadly tripartite strain distribution, with extensional (e.g. normal faults), translational and contractional (e.g. folds and thrusts) domains, along with a radial frontally emergent zone. We also show how strain is preferentially concentrated around intra‐MTC rafted‐blocks due to their kinematic interactions with the underlying basal shear zone. Overall, and even when volume loss within the frontally emergent zone is included, a strain difference between extension (1.6–1.9 km) and contraction (6.7–7.3 km) is calculated. We attribute this to a combination of distributed, sub‐seismic, ‘cryptic’ strain, likely related to de‐watering, grain‐scale deformation and related changes in bulk sediment volume. This work has implications for assessing MTCs strain distribution and provides a practical approach for evaluating structural interpretations within such deposits. 相似文献
993.
994.
Solar System Research - This article describes the results of the Phobos 2 interplanetary mission, launched in 1988, and presents some prospective scenarios for studying near-Mars space, including... 相似文献
995.
Eismont N. A. Zasova L. V. Simonov A. V. Kovalenko I. D. Gorinov D. A. Abbakumov A. S. Bober S. A. 《Solar System Research》2019,53(7):578-585
Solar System Research - The article describes the trajectory scenario for the Venera-D mission. The main aspects of optimal launch dates are considered. A scenario, which enables insertion of an... 相似文献
996.
Solar System Research - The article considers the problem of controlling the relative motion of spacecraft (SC) flying in tandem for interferometric imaging. The effect of the geometry of the... 相似文献
997.
Solar System Research - The article discusses the problems of controlling the relative motion of spacecraft (SC) in a tandem flight configuration. Flight configurations of two SC that form the... 相似文献
998.
Shock is often given as the cause for many observations in meteorites due to the assumed previous exposure of most meteorites to at least one impact event that ultimately led to their ejection from their parent body. Here we present electron backscatter diffraction (EBSD) results on a substantially shocked dunitic achondrite, chassignite Northwest Africa (NWA) 8694, and question the general culpability of shock exposure for the formation of preferred orientation fabrics of meteoritic olivine crystals. Despite the ubiquitous presence of substantial shock indicators, the EBSD results for NWA 8694 reveal an absence of preferred orientation of olivine crystals, displaying instead an overall random fabric. We propose that the passage of shock waves through olivine crystals within a solid, crystalline, dunitic rock does not produce an overall preferred orientation, nor is it likely to actively form a whole‐rock random fabric but instead has likely no bearing on the formation of olivine orientation fabrics. 相似文献
999.
Astronomy Letters - The formation of hydrogen emission lines in the magnetospheres of young stars is considered. The magnetosphere is assumed to be formed by a dipolar magnetic field whose axis is... 相似文献
1000.
Astronomy Letters - We have investigated the methanol CH3OH lines at frequencies of 19.967 GHz [21-30 E(vt = 0) transition] and 20.971 GHz [101-112 E+(vt = 1) transition] toward the massive region... 相似文献