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961.
962.
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
963.
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
964.
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
965.
966.
Qadri S. M. Talha Islam Md. Aminul Shalaby Mohamed Ragab 《Natural Resources Research》2019,28(2):369-392
Natural Resources Research - This study addresses the three-dimensional (3D) petrophysical modelling and volumetric analysis of the Farewell Reservoir in the Kupe Field in the southern Taranaki... 相似文献
967.
Izvestiya, Atmospheric and Oceanic Physics - In this paper we study the evolution of the matter distribution pattern of ink droplets falling freely into calm water and forming a cumulative back jet... 相似文献
968.
Ilin N. V. Shatalina M. V. Slyunyaev N. N. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(5):446-452
Izvestiya, Atmospheric and Oceanic Physics - On the basis of a parametrization of the ionospheric potential (IP), the seasonal dynamics of the diurnal IP variation for 2016–2017 is simulated... 相似文献
969.
Zakharov V. S. Simonov D. A. Bryantseva G. V. Kosevich N. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(7):721-730
Izvestiya, Atmospheric and Oceanic Physics - The results of the fractal analysis of a drainage network reconstructed using a digital elevation model and the structural and geomorphological analysis... 相似文献
970.
K. M. Evans 《Geological Journal》1983,18(4):297-305
The Lynton Beds represent shallow marine sediments with a restricted fauna dominated by brachiopods. The age indicated by the brachiopod fauna is late Emsian, although the possibility of a younger date for the uppermost horizons cannot be discounted. 相似文献