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91.
A simplified empirical equation is developed for widespread prediction of dynamic catchment response time. This model allows for time-to-peak prediction to evolve from static, lumped models, thereby providing a single value for any storm within a given catchment, using a single set of input parameters, that can be applied to a dynamic model, thus accounting for the variability between storm sizes and catchment moisture conditions. These dynamic prediction methods are translated to North America for the first time. This allows the concepts and prediction methods for catchment response time prediction previously established for the United Kingdom (UK), to be translated to a simple empirical equation for use in North America, through the use of selected study areas in Canada and the United States. This reconfigured model is statistically successful in both the UK and North America and allows for a straightforward implementation of dynamic time-to-peak prediction. Further, the reconfigured model introduces the use of a runoff coefficient (Rc) to encompass historical catchment wetness, increasing the ease of incorporating antecedent moisture condition into predictions. 相似文献
92.
Quaternary reactivation of Tertiary faults in the southeastern Korean Peninsula: Age constraint by optically stimulated luminescence dating 总被引:1,自引:0,他引:1
Jin-Han Ree Young-Joon Lee Ed J. Rhodes Youngdo Park Sung-Tack Kwon Ueechan Chwae Jeong-Soo Jeon Bongjoo Lee 《Island Arc》2003,12(1):1-12
Abstract Two groups of Quaternary faults occur in the southeastern Korean Peninsula. The first group is north-northeast-striking, high-angle dextral strike–slip faults. The second group is north-northeast-striking, low-angle reverse faults that represent the reactivation of the pre-existing normal faults. Optically stimulated luminescence dating of Quaternary sediments cut by one of the reverse faults constrains the faulting age to post-32 Ka. These faults seem to be capable of further slip under the current tectonic stress regime, as determined by recent earthquake events in northeast Asia. Therefore, the traditional concept that the southeastern Korean Peninsula is seismically stable should be reappraised. 相似文献
93.
Mathematical Geosciences - 相似文献
94.
Subduction factory processes beneath the Guguan cross-chain, Mariana Arc: no role for sediments, are serpentinites important? 总被引:1,自引:0,他引:1
Robert J. Stern Ed Kohut Sherman H. Bloomer Matthew Leybourne Matthew Fouch Jeff Vervoort 《Contributions to Mineralogy and Petrology》2006,151(2):202-221
We need to understand chemical recycling at convergent margins and how chemical interactions between subducted slab and the
overlying mantle wedge affect mantle evolution and magmagenesis. This requires distinguishing contributions from recycled
individual subducted components as well as those contributed by the mantle. We do this by examining magmatic products generated
at different depths above a subduction zone, in an intra-oceanic arc setting. The Guguan cross-chain in the intra-oceanic
Mariana arc overlies subducted Jurassic Pacific plate lithosphere at depths of ~125--230 km and erupts mostly basalt. Basalts
from rear-arc volcanoes are more primitive than those from the magmatic front, in spite of being derived by lower degrees
of melting of less-depleted mantle. Rear-arc magmas also show higher temperatures and pressures of equilibration. Coexisting
mineral compositions become more MORB- or OIB-like with increasing height above the subduction zone. Trace element and isotopic
variations indicate that the subduction component in cross-chain lavas diminishes with increasing depth to the subduction
zone, except for water contents. There is little support for the idea that melting beneath the Mariana Trough back-arc basin
depleted the source region of arc magmas, but melting to form rear-arc volcanoes may have depleted the source of magmatic
front volcanoes. Enrichments in rear-arc lavas were not caused by sediment melting; the data instead favor an OIB-type mantle
that has been modestly affected by subduction zone fluids. Our most important conclusion is that sediment fluids or melts
are not responsible for the K--h relationship and other cross-chain chemical and isotopic variations. We speculate that an
increasing role for supercritical fluids released from serpentinites interacting with modestly enriched mantle might be responsible
for cross-chain geochemical and isotopic variations.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
95.
Ed Sobey 《Journal of Oceanography》1975,31(6):235-242
Composite pictures of the areal extent of Antarctic sea ice derived from satellite photographs, show that the growth and the rate of growth of the pack ice compare favorably to the values previously estimated on other bases. Anomalous growth patterns are found in the Weddell Sea. Possible causes of this anomaly include surface and subsurface advection of ice crystals. The rate of retrogradation of the pack ice is found to exceed the rate of progradation. 相似文献
96.
Bengt Edĺen 《Solar physics》1972,24(2):356-367
Values of the level intervals in the ground configurations 2s
2 2p
2, 2s
2 2p
3 and 2s
2 2p
4 have been critically compiled from laboratory observations and from observations of nebular and coronal forbidden transitions. The data are represented within experimental errors by means of semi-empirical extrapolation formulae which contain from 3 to 5 adjusted parameters. The results provide means for checking laboratory and astrophysical identifications and measurements. Tables of best level values are given for the configurations concerned. 相似文献
97.
Paul A. Abell David J. Korsmeyer Rob R. Landis Thomas D. Jones Daniel R. Adamo David D. Morrison Lawrence G. Lemke Andrew A. Gonzales Robert Gershman Theodore H. Sweetser Lindley L. Johnson Ed Lu 《Meteoritics & planetary science》2009,44(12):1825-1836
Abstract— A study in late 2006 was sponsored by the Advanced Projects Office within NASA's Constellation Program to examine the feasibility of sending the Orion Crew Exploration Vehicle (CEV) to a near‐Earth object (NEO). The ideal mission profile would involve two or three astronauts on a 90 to 180 day flight, which would include a 7 to 14 day stay for proximity operations at the target NEO. This mission would be the first human expedition to an interplanetary body beyond the Earth‐Moon system and would prove useful for testing technologies required for human missions to Mars and other solar system destinations. Piloted missions to NEOs using the CEV would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while conducting in‐depth scientific investigations of these primitive objects. The main scientific advantage of sending piloted missions to NEOs would be the flexibility of the crew to perform tasks and to adapt to situations in real time. A crewed vehicle would be able to test several different sample collection techniques and target specific areas of interest via extra‐vehicular activities (EVAs) more efficiently than robotic spacecraft. Such capabilities greatly enhance the scientific return from these missions to NEOs, destinations vital to understanding the evolution and thermal histories of primitive bodies during the formation of the early solar system. Data collected from these missions would help constrain the suite of materials possibly delivered to the early Earth, and would identify potential source regions from which NEOs originate. In addition, the resulting scientific investigations would refine designs for future extraterrestrial resource extraction and utilization, and assist in the development of hazard mitigation techniques for planetary defense. 相似文献
98.
99.
Carlos Sancho Jos Luis Pea Felipe Rivelli Ed Rhodes Arsenio Muoz 《Journal of South American Earth Sciences》2008,26(1):68-77
The development and evolution of the Tilcara alluvial fan, in the Quebrada de Humahuaca (Andean Eastern Cordillera, NW Argentina), has been analysed by using geomorphological mapping techniques, sedimentological characterisation of the deposits and OSL chronological methods. It is a complex segmented alluvial fan made up of five evolutionary stages (units Qf1, Qf2, Qf3, Qf4 and Qf5) developed under arid climatic environments as well as compressive tectonic conditions. Segmentation processes, including aggradation/entrenchment cycles and changes in the location of the depositional lobe, are mainly controlled by climatic and/or tectonic changes as well as channel piracy processes in the drainage system. Alluvial fan deposits include debris flows, sheet flows and braided channel facies associated with high water discharge events in an arid environment. The best mean OSL age estimated for stage Qf2 is 84.5 ± 7 ka BP. In addition, a thrust fault affecting these deposits has been recognized and, as a consequence, the compressive tectonics must date from the Upper Pleistocene in this area of the Andean Eastern Cordillera. 相似文献
100.