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131.
Relationships between crater size and ejecta-blanket areal extents imply a maximum ejecta-blanket thickness or maximum rim height for Martian rampart craters. The limiting thickness is encountered only for craters exceeding 6 km diameter. Although smaller rampart craters have ejecta which appears to have undergone flow during emplacement, the larger craters have an additional component of flow, namely, internal flow of the ejecta caused by the greater weight of their thicker ejecta deposits. Pedestal craters most likely result from impacts into less volatile-rich substrates which produce a less fluidized ejecta and, consequently, no flow lobes. 相似文献
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Les Basher Raphael Spiekermann John Dymond Alex Herzig Ella Hayman Anne-Gaelle Ausseil 《新西兰海洋与淡水研究杂志》2020,54(3):490-511
ABSTRACT SedNetNZ is used to model the effect of erosion control undertaken under the Sustainable Land Use Initiative (SLUI) and predict the effect of climate change on sediment load in the Manawatū–Whanganui region. Sediment load in 2004 is estimated at 13.4?Mt?yr?1; by 2018, ≈5000?km2 of land had farm plans implemented and annual sediment load reduced by 6.2% of the 2004 load. If SLUI stops at the 2018 level of implementation, by 2038 it is predicted to achieve a 15.7% reduction in annual sediment load. If SLUI continues to implement farm plans, 7949?km2 of land will be treated by 2043 and annual sediment load could be reduced by a further 14.7%. Climate change is predicted to substantially increase sediment loads. By 2043 annual sediment load for the region is predicted to increase, compared to 2004, by between 8.3 and 23.7%. However, this can largely be offset by SLUI works. By 2090 an annual sediment load increase of between 53 and 224% due to climate change is predicted. The results suggest climate warming may dominate changes in sediment load in the future. 相似文献
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Aguilar-Meléndez Armando Pujades Lluis G. Barbat Alex H. Monterrubio-Velasco Marisol de la Puente Josep Lantada Nieves 《Natural Hazards》2022,110(3):1649-1691
Natural Hazards - There are personal and institutional decisions that can increase the seismic resilience of the buildings in a city. However, some of these decisions are possible if we have basic... 相似文献
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Talebi Hassan Peeters Luk J. M. Otto Alex Tolosana-Delgado Raimon 《Mathematical Geosciences》2022,54(1):1-22
Mathematical Geosciences - Spatial data mining helps to find hidden but potentially informative patterns from large and high-dimensional geoscience data. Non-spatial learners generally look at the... 相似文献
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Alex Ruzicka Jeffrey Grossman Audrey Bouvier Christopher D. K. Herd Carl B. Agee 《Meteoritics & planetary science》2015,50(9):1661-1661
Meteoritical Bulletin 101 contains 2639 meteorites accepted by the Nomenclature Committee in 2012, including 1 fall (Battle Mountain), with 2308 ordinary chondrites, 156 carbonaceous chondrites, 63 HED achondrites, 17 relict meteorites, 16 Rumuruti chondrites, 15 enstatite chondrites, 15 ureilites, 10 iron meteorites, 9 lunar meteorites, 9 primitive achondrites, 8 ungrouped achondrites, 7 mesosiderites, 4 Martian meteorites, and 2 Pallasites, and with 1812 from Antarctica, 437 from Asia, 301 from Africa, 43 from South America, 21 from Europe (including Russia), 21 from North America, 3 from Oceania, and 1 from unknown. Information about approved meteorites can be obtained from the Meteoritical Bulletin Database (MBD) available on line at http://www.lpi.usra.edu/meteor/ . 相似文献
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