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We conducted a detailed analysis of along-trench variations in the flexural bending of the subducting Pacific Plate at the Tonga-Kermadec Trench. Inversions were conducted to obtain best-fitting solutions of trench-axis loadings and variations in the effective elastic plate thickness for the analyzed flexural bending profiles. Results of the analyses revealed significant along-trench variations in plate flexural bending: the trench relief(W_0) of 1.9 to 5.1 km;trench-axis vertical loading(V_0) of –0.5×(10)~(12) to 2.2×(10)~(12) N/m; axial bending moment(M_0) of 0.1×(10)~(17) to 2.2×(10)~(17) N;effective elastic plate thickness seaward of the outer-rise region(T_e~M) of 20 to 65 km, trench-ward of the outer-rise(T_e~m) of 11 to 33 km, and the transition distance(X_r) of 20 to 95 km. The Horizon Deep, the second greatest trench depth in the world, has the greatest trench relief(W_0 of 5.1 km) and trench-axis loading(V_0 of 2.2×(10)~(12) N/m); these values are only slightly smaller than that of the Challenger Deep(W_0 of 5.7 km and V_0 of 2.9×(10)~(12) N/m) and similar to that of the Sirena Deep(W_0 of 5.2 km and V_0 of 2.0×(10)~(12) N/m) of the Mariana Trench,suggesting that these deeps are linked to great flexural bending of the subducting plates. Analyses using three independent methods, i.e., the T_e~M/T_e~m inversion, the flexural curvature/yield strength envelope analysis, and the elasto-plastic bending model with normal faults, all yielded similar average Te reduction of 28%–36% and average Te reduction area S￠Te of 1 195–1 402 km~2 near the trench axis. The calculated brittle yield zone depth from the flexural curvature/yield strength envelope analysis is also consistent with the distribution of the observed normal faulting earthquakes. Comparisons of the Manila, Philippine, Tonga-Kermadec, Japan, and Mariana Trenches revealed that the average values of T_e~M and T_e~m both in general increase with the subducting plate age. 相似文献
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清晨,当你一觉醒来,推开窗户呼吸外面新鲜空气时,你可曾想到这时你可能正处在一层可怕的恒星（太阳）大气袭击之中？也许你对此话嗤之以鼻,可是当你看到地平线上极光在飞舞时,知道太阳活动在你头顶上空和周围引起种种爆裂时,当电视里空间气象预报员向宇航员发出警告说：“爆发了巨大的太阳耀斑”时,你就知道此话不谬了。 相似文献
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YIN Shu-bai LU Xian-guo 《中国地理科学(英文版)》2006,16(1):56-62
1 INTRODUCTION There is no single and universally recognized wetland definition so far. More than 50 of wetland definitions have been developed (YANG, 2002; DUGAN, 1993; MITCH and GOSSELINK, 1996; NRC, 1995). Because wetlands form part of a continuous gradient between u- plands and open water, the problem on wetland defini- tion usually arises on the edges of wetlands, toward ei- ther wetter or drier conditions (NRC, 1995; MITSCH and GOSSELINK, 1996). What frequency, dept… 相似文献
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高精地图逐渐成为自动驾驶不可或缺的组成部分,但是其数据模型和表达方式尚未形成统一标准,特别是在生产制作和数据交换阶段,缺乏具备通用性和大规模应用能力的数据模型.针对这一问题,本文分析了当前主流高精地图数据模型NDS、OpenDRIVE和l anel et的优缺点,提出了一种通用化的高精地图数据模型Whu map model.车道模型方面,采用车道组为数据管理单元,由同一路段上的一个或者多个车道组成.车道由车道的左边界线、右边界线、车道中心线、车道属性构成.通过多种常见车道数变化场景下的车道拓扑构建,验证了该模型在表达上的有效性和稳健性.交通标志物模型方面,定义了地面标志物和交通标志牌,分别表达形状、类型、语义以及与道路、车道的关联关系等内容.通过大规模数据制作、NDS和OpenDRIVE格式编译,以及基于ADASIS V3协议的电子地平线应用试验,验证了Whu map model模型的实用性和有效性.Whu map model可以作为通用的交换规格,也可以应用到高精地图生产制作的各个阶段,同时向下兼容、易于扩展,有助于实现高精地图数据模型标准化,从而推进高精地图的规模化生产和应用. 相似文献
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<正>2010年4月20日,一个属于英国石油公司名为"深水地平线"的钻井平台突然在美国路易斯安那州威尼斯东南约82公里的海域处爆炸,造成了11人失踪,并导致墨西哥湾地区被大面积浮油覆盖,经济和生态环境遭到威胁。 相似文献
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