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[转载]Unusual Amounts Of Lightning Storms Invade Hawaii
zuojun 2011-6-5 05:47
Watch this news clip. http://www.kitv.com/video/28129802/detail.html POSTED: 10:47 pm HST June 3, 2011 UPDATED: 10:48 pm HST June 3, 2011
个人分类: Uniquely Hawaii|1546 次阅读|0 个评论
Evaluations of Spring 2011 Courses (at U. Hawaii)
zuojun 2011-6-3 11:33
I think I will just share two comments with you here. "Started class early - unacceptable as many students have class before. She didn answer any questions. RUDE! ..." "I really enjoyed learning from Dr. Yu. I want to say I appreciate her + her knowledge very much and apologize for some of the other students in the class. Thank you! I learned a lot." ps. I feel sorry that some students felt that way about me. I could not imagine how they must have suffered...
个人分类: Uniquely Hawaii|2109 次阅读|0 个评论
地幔转换带不连续面地震成像结果指示夏威夷西部存在热地幔
热度 3 chunyinzhou 2011-5-31 08:39
地幔转换带不连续面地震成像结果指示夏威夷西部存在热地幔
地幔转换带不连续面地震成像结果指示夏威夷西部存在热地幔 Seismic imaging of transition zone discontinuities suggests hot mantle west of Hawaii Q. Cao 1 , * , R. D. van der Hilst 1 , * , M. V. de Hoop 2 , and S.-H. Shim 1 太平洋中部夏威夷热点通常都被认为是来自深部地幔物质穿越上地幔在地表形成的,但是要在地震学上对plume进行严格的约束却是比较困难的事情。来自美国麻省理工大学(MIT)的van der Hilst研究小组( http://quake.mit.edu/hilstgroup/robspage/ ),通过地球物理方法,对夏威夷周围地区地幔转换带的结构(不连续面深度,转换带厚度)进行了研究,并对转换带边界的异常进行了讨论分析,他们认为这些异常是由于高温条件下的地幔矿物相变(橄榄石和石榴石体系相变)形成的,但是这些热物质并不是来自于下地幔,这与传统地球化学研究观点是不同的。这一研究成果发表在2011年5月27日最新一期Science杂志上。 (延伸阅读): Hawaii heat source debated : http://www.sciencenews.org/view/generic/id/74845/title/Hawaii_heat_source_debated Science原文链接: http://www.sciencemag.org/content/332/6033/1068.full Supporting Online Material : www.sciencemag.org/cgi/content/full/332/6033/1068/DC1 PDF文档: http://quake.mit.edu/hilstgroup/robspage/PapersPDF/2011Science_Hawaii_I.pdf 全文翻译:周春银 夏威夷热点 (hotspot) 通常被认为是由来自地幔深部的热物质形成的,但是要通过地震学方法来探测这样一个热柱却是很困难的。为了研究这样的热异常,我们利用 SS 波逆散射方法对太平洋中部之下的地震不连续面进行了成像,这些不连续面我们可以用地幔岩成分的地幔中的橄榄石和石榴石的相变来解释。 在夏威夷西部地幔转换带中出现的 800-2000 km 的热异常 (ΔT max ~300-400 K) ,说明这些热物质并不是从下地幔通过较细的垂直热柱 (plume) 上升上来的,而是在其进入流向夏威夷或者其他岛屿地区的热流之前就已堆积在转换带底部。这说明夏威夷熔岩的地球化学特征并不能直接约束下地幔(地球化学)域。 地幔柱 (mantle plume) 仍然是地球深部研究 (studies of Earth’s deep interior, SEDI) 中尚未完全解决的问题,作为与地幔柱有关的热点活动的原型,夏威夷长期以来都是争论的焦点。在运动的太平洋板块下面有一个来自下地幔的细细的热柱 (1-5) ,这样的经典观点已经被广泛运用于夏威夷熔岩 (6-7) 、地幔柱 - 板块相互作用 (8) 以及对流地幔风对地幔柱形态和海山链发育的影响作用 (9,10) 等方面的研究。深源地幔柱的经典一直都受到质疑,但是,仍有一些其他的代表性的解释,如来自转换带底部附近热边界处的上升流 (11) 和浅部地幔过程 (12) 。有关传说中的地幔柱的存在、定位和起源深度的层析成像证据仍然是比较模糊的 (13-17)(SOM text 1) 。 与深源地幔柱相关的温度异常会影响到矿物相边界 ( 压力引起的 ) 的深度,这可以通过地震波的反射或转换来确定 (18) 。非常重要的成像目标为在 410km 和 660km 深度附近 (Mg,Fe) 2 SiO 4 体系的橄榄石 - 瓦兹利石相变和后尖晶石相变 (19) 。由于他们具有相反的克拉伯龙斜率 (Clapeyron slope) ,高温将会使前者下降而使后者抬升 (SOM text 2) 。接收函数方法研究 (P-S 转换 ) 显示在夏威夷西南部 (20-22) 以及夏威夷岛链 (23) 之下存在较薄的地幔转换带。这表明存在高温环境,但是这些异常在侧向上的范围还难于确定,因为在岛屿及其周围地区地震台网还不够。 在超出接收函数方法之外,转换带不连续面可以利用下面的 S d S 反射 (d 是反射深度 ) 来成像确定,它在远离研究区域之外作为接收器面反射 SS 波的前驱波 (precursors) 而到达 (Fig.1) 。传统方法通过沿大范围 (10 -20 ) 区域叠加镜像 ( 像镜子一样 )SS 反射来提高较弱的信号 (24-28) 。这样的平均化会导致较低的空间分辨率,但是还并未得到夏威夷之下明显的 410 和 660km 不连续面 (SOM text 1) 。本文我们使用了 SS 波场的三维 (3D) 逆散射方法,以及被称为 GRT(generalized Radon transform)(29)(SOM text 3) 的方法 ( 改自碳氢化合物勘探方法 ) 。这也会产生数据冗余,但是不再在立体空间 (bins) 内叠加静态相,它结合了与单一成像点散射波相关的信号。利用 SS 前驱波进行 GRT 成像的可行性最早是在一个远离已知的热上涌和下降的大洋区域得到证明的 (30) 。 Fig. 1 Left: (Top) Map of study region (175° to 214°E; 12° to 26°N; Mercator projection, perspective view); (middle) geographical distribution of ~170,000 surface mid-points of SS waves (the darker the shading, the denser the coverage (SOM text 3.2); (bottom) path geometry of underside reflections at the surface ( SS ) and an upper-mantle discontinuity ( S 410 S or S 660 S ); precursor stack showing signal associated with S 660 S , S 410 S , and SS waves . Right: (Top) Geographical distribution of ~4800 sources (red symbols) and ~2250 receivers (blue) from which data are used, and which produces the data coverage shown on the left; (bottom) schematic view of ray geometry of SS , S 410 S, and S 660 S sampling the upper-mantle transition zone below the imaging area (UM, upper mantle; TZ, transition zone; LM, lower mantle). 我们利用 SS 波场 ~170000 宽频带 (20-50s) 记录来对夏威夷及其附近区域的转换带进行成像,这些记录来自于太平洋地区附近总共 ~2250 地震台站 ~4800 次地震记录 ( 震级 m b 5.2, 震源深度 75km)(Fig.1, SOM text 3.1) 。数据覆盖在大多数研究区域都是足够的,但是向西南方向会降低 (SOM fig.S6, C and F) 。在 250-950 km 深度范围、 0.5×0.5 经纬度格子内 GRT 得到弹性差异的 1D 剖面 (SOM text 3.2 and 3.3) 。这些图像,经过 3D 地幔不均一性 ( 利用不同的层析成像模型 ) 和 SS 反射点深度区域变化的校正,可以在与接收函数方法相当的辐射分辨率条件下确定边界。这些紧密隔开的反射剖面显示了 410km 和 660km 不连续面的深度变化 (topography) ,并阐明了在其他深度可能会被当作噪声而处理的构造。我们利用抽样分析来了解这些成像结果的可靠性 (SOM text 3.5) 。 3D 成像的横截剖面如穿过夏威夷的剖面 (Fig.2) 显示了多个散射水平面。除了 410km 附近和 650-700km 深度范围内的反射体之外,在大约 350 、 500 、 550 以及 800-900km 深度附近也有散射产生。大多数都是连续的并具有明显的 topography ,但是有些仍然是断断续续的或者分散的。我们这里主要关注转换带的通常边界。在 Fig.2B 中我们追踪横截剖面中的 410km 和 660km 不连续面,从所有网格点选取的深度得出不连续面深度 (Fig.3A and B) 、转换带厚度 (Fig.3C) 和深度相关性 (Fig.3D) 图像。 Fig. 2 Seismic section (E-W) across Hawaii (see Fig. 3 for section location). ( A ) Seismic image superimposed on tomographically inferred wave-speed variations ( 13 ). ( B ) Enlargement of image between 370- and 760-km depth, with interpretation of 410 (dashed green line), 520 (blue), and 660 (red) discontinuities. The depth profiles are corrected for 3D mantle heterogeneity (from tomography) and for the depth to the ocean floor where SS reflections occur. Inverse scattering does not assume contiguous reflectors (SOM text 3.2), but alignment suggests lateral continuity. Interfaces appear as a pulse with sidelobes, the width of which depends on frequency of the data and the angle at which image points are sampled ( 30 ). Horizontal resolution (which depends on illumination) is estimated to be on the order of a few hundred kilometers in the center of the study region (degrading to ~500 km toward the southwest owing to reduced sampling). I, II, and III mark regions discussed in the main text. The image gathers at 190°E and 200°E (highlighted in section on the right) are discussed in SOM text 3.3 and fig. S7). 410km 不连续面深度变化于 395-430km 之间 ( 侧向范围 500-750km) , 660km 不连续面深度变化于 640-705km 之间 ( 侧向上更平滑一些 ) 。夏威夷下面之下及以东 ( 区域 I) , 660km 不连续面比全球平均值 (~650km) 略浅一点。夏威夷和 165 W 之间 ( 区域 II) , 660km 不连续面更加异常 (~640km) ,这证实了 P-S 转换的观测结果 (20-23) ,但是将异常延伸到比原来更向西的区域。 167 W-179 W 之间 ( 区域 III) , 410km 不连续面达到了 430km 而 660km 不连续面出现在异常深度 (~700km) 。 180 以西区域界面接近全球平均深度 (29) 。 410km 和 660km 不连续面的区域平均深度分别为 413km 和 665km ,后者在区域 III 中具有较大值。转换带在夏威夷之下以及西北部较薄而在区域 III 中较厚 (Fig.3C) 。 410km 和 660km 不连续面在区域 I 和 II 中呈负相关关系,而在区域 III 中呈正相关关系 (Fig.3D) 。 Fig. 3 Discontinuity depths, transition zone thickness, and depth correlations in the study region. ( A ) Topographic map of 410 (regional average 413 km) and ( B ) 660 (regional average 665 km). Thick black solid line depicts location of E-W cross section in Fig. 2 , and thin black line in (B) indicates the location (at 700-km depth) of the mantle plume identified in ( 16 ); see also fig. S2B. I, II, and III mark the regions discussed in the main text. ( C ) The difference between 410 and 660 depths suggests that a relatively thin transition zone (passing through Hawaii) surrounds a thick transition (between 180° and 195°E, Region III). ( D ) Correlation between 410 and 660 depth variations (in regions where 410 and 660 topography exceeds 2.5 and 5 km, respectively). Interface depths are (weakly) negatively correlated beneath Hawaii, but conspicuous positive correlation appears in region III. In (A) to (C), regions where the 410 or 660 could not be identified unambiguously are left blank, and light shading indicates areas of relatively poor data coverage. 有两种类型的人为因素会影响成像的质量和准确性。首先,如果体积波速与我们用来作走时计算的值不同时,边界深度就会出现偏离 (Something text 3.4) 。这一效应非常小而难于解释区域 II 和 III 内较大的深度变化,但也可能存在某种平衡 (trade-off) 。在空间上连续的深度变化达 10km 或以上则被认为是有意义的 (30) ,但是作为保守的解释,对界面深度的估计被当作上限。其次,较稀疏的采样 ( 如夏威夷西部 ) 会降低降噪作用和空间分辨率。目测显示收集的图像 (Something text 3.3) 在大多数研究区域都是可靠的,抽样表明在区域 I 、 II 和 III 内一级观测在 95%(2σ) 自信度条件下都是可靠的 (SOM text 3.5) 。但是夏威夷西部部分深部构造处于在目前有效数据条件下可分辨的边缘。 即使存在这些不确定性因素,一级观测仍表明,夏威夷位于一个由异常较深的 410km 和 660km 不连续面以及很厚的转换带 ( 区域 III) 所构成区域东缘之上,周围是较浅的 660km 不连续面和减薄的转换带 ( 区域 I,II) 。这一预料之外的结构复杂性表明,夏威夷及其周缘地区下地幔上部边界处存在着较大的温度变化 ( 以及可能的成分变化 ) 。为了估算转换带顶部 (ΔT 410 ) 和底部 (ΔT 660 ) 的原位 (in situ) 地幔温度,我们使用的是地幔岩成分地幔中橄榄石和石榴石相变的压力 - 温度关系 ( 即克拉伯龙斜率 Γ)(SOM text 2) 。在这里并不需要非地幔岩成分来解释一级观测结果。 我们首先利用 (Mg,Fe) 2 SiO 4 橄榄石相变来解释观测结果,即橄榄石 - 瓦兹利石相变 (31) ,瓦兹利石 - 林伍德石相变 (32) ,林伍德石 - 钙钛矿 + 铁方镁石相变 ( 后尖晶石相变 ) (33) 。根据这些斜率所得到的温度地图显示,在夏威夷下面及以东地区 ( 区域 I) 存在较弱的扰动 (ΔT 410 ≈ΔT 660 ≈150K) ,但是更远的西部存在较大的异常。如果认为区域 II 较浅的 660km 不连续面是后尖晶石相变边界的上拱引起的,那么可以得到 ΔT 660 ≈300K ,与前人估计 (20,21) 一致,而较低的 ΔT 410 则说明比较明显的异常仅仅局限于转换带底部。但是 3D 结构却是很复杂的,更北地区较深的 410km 不连续面和较浅的 660km 不连续面则说明夏威夷岛链下面上地幔中具有很高的温度 (23) 。 较深的 660km 不连续面 ( 区域 III) 仍然是难于解释的谜团。对于上述 Γ p-sp 来说, 640-700km 之间的后尖晶石相变深度变化意味着温差达 ~850K 。在远离板块边缘的地区存在这样巨大的梯度是不现实的。如果 660km 不连续面之上 ( 或下 ) 波速比 3D 地幔校正中根据层析成像所推测的值要更低 ( 或高 ) ,那么 660km 不连续面可能会被高估。也有可能存在某些平衡,但是用这种方法来解释所有信号特征则需要一些似是而非的地震波和 ( 可能 ) 热异常 (SOM text 3.4) 。对于 Γ p-sp 、 ΔT 660 和上地幔波速真实值来说,后尖晶石相变并不能很好的解释 700km 深度附近的界面。 较大的 410km 和 520km 不连续面深度说明区域 III 转换带温度升高。多顶砧 (multi-anvil) 实验结果 (34-36) 证明,在高温条件下存在不同的相关系以及 Al 分配作用会增加后石榴石相变 (post-garnet transitions) 时的 ( 地震波 ) 突变。这类实验都是非常具有挑战性的,但是相关系的一些重要方面,如该正克拉伯龙斜率 (Γ p-gt ) 的大小、化学成分对其位置的影响以及 ( 相对于后尖晶石相变而言 ) 后石榴石相变的地震学可探测性 (seismic detectability) ,仍然不是特别清楚 (SOM text 2) 。后石榴石相变可能存在于热地幔中比正常地幔后尖晶石相变更深的位置,这已经被用来解释深部 660km 不连续面的发现 (24,27) 。我们的图像则描述了从后尖晶石相变 ( 区域 II) 到后石榴石 ( 区域 III) 的侧向变化。考虑到可能存在的某种平衡 (trade-off) 以及克拉伯龙斜率和 ( 地幔岩中 )Al 2 O 3 含量的不确定性,对后石榴石相变的 ΔT 660 的估计仍然带有很多不确定性,但是 Γ p-gt =3.0 MPa/K (37) 将会产生一个 450K 的上限 ( 下限由区域 II 后尖晶石相变温度所确定 ) 。 夏威夷西部地幔 660km 深度附近是很热的,该区域至少有 800km 宽 ( 如果局限于区域 II) ,但是也可能宽达 2000km ( 如果包括区域 III) ,该界面说明热物质在下地幔顶部堆积并扩散开来,热点火山作用可以由转换带底部的次级上升流 (5,38)(SOM text 5) 提供物质来源 (Fig.4) 。这与夏威夷西南下地幔地幔柱的层析成像观点 (16,17) 是不同的,但是目前还没有可用的走时数据来解释地幔中连续的地幔柱似的结构和不同深度的分散的异常 (SOM text 1) 。 Fig. 4 Cartoon of broad anomaly near base of the transition zone west of Hawaii, superimposed on a scattering image ( Fig. 2 ). Green, blue, and red lines depict interfaces near depths of 410, 520, and 660 km. The deep 410 and 520 west of Hawaii suggest higher-than-average temperatures (Δ T 410 ≈ 200 K) in the upper mantle and transition zone, but with current data coverage we cannot distinguish between a large single anomaly and multiple smaller ones. Updoming of the 660 beneath region II is consistent with elevation of post-spinel transition in hot mantle regions (with Δ T 660 ≈ 300 K), whereas deepening to ~700 km beneath III (red dashed line) may indicate change of dominant transition system to garnet (with Δ T 660, max ≈ 450 K). The positive Clapeyron slope of the latter may aid flux of lower mantle material into the transition zone (thin red arrows). Pathways of flow from the deep anomaly to Earth’s surface are not resolved by the data used, but Hawaii volcanism may result from upwellings from the (edge of the) broad anomaly (for instance, just east of Hawaii, region I, Fig. 3 ). 不连续面层析成像反应的是局部环境,其自身并不能确定热异常的来源、寿命和深度范围。但是温度差异以及地表火山作用所需要的持续热流 ( 如果他们的确是相关的话 ) 表明这并不是一个孤立的、短暂的结构,它可以从下面如通过热柱或者大尺度 ( 热化学的 ) 地幔穹窿来更新 (5) 。如果存在联系,由转换带产生的短暂的失稳特征将有助于解释夏威夷 - 皇帝海山链演化 ( 随年代推进 ) 过程中的不规则性 (10) 。此外,主要相变体系在侧向上的变化可以影响上下地幔之间的物质交换。根据后石榴石相变的宽度、每个高温相变的密度差异 ( 即尖晶石相 ↔ 石榴石 + 镁方铁矿 ↔ 钙钛矿 + 镁方铁矿 ) 、 Γ p-gt 的值和化学成分的综合作用,后石榴石相变可以促进次级上升流的形成,因而也有助于形成区域 III 上地幔温度的提高、正大地水准面异常以及可能的远离海山链的深海测量特征的富集。最后,任何在 660km 不连续面处的下地幔流动临时富集都表明存在管流或者说地幔柱的成带分布 (7,39-41) 肯定是浅部地幔现象,而地表熔岩的同位素特征并不能用来构建下地幔中的地球化学域。 References and Notes 1. J. T. Wilson , Can. J. Phys. 42 , 893 (1963). 2. W. J. Morgan, Convection plumes in the lower mantle. Nature 230 , 42 (1971). doi:10.1038/230042a0 CrossRef 3. G. F. Davies, Ocean bathymetry and mantle convection 1. Large-scale flow and hotspots. J. 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Christensen, The dynamical origin of Hawaiian volcanism. Earth Planet. Sci. Lett. 171 , 517 (1999). doi:10.1016/S0012-821X(99)00179-X CrossRef Web of Science 9. B. Steinberger , R. J. O’Connell , Advection of plumes in mantle flow: Implications for hotspot motion, mantle viscosity and plume distribution. Geophys. J. Int. 132 , 412 (1998). doi:10.1046/j.1365-246x.1998.00447.x CrossRef Web of Science 10. J. Tarduno , H.-P. Bunge , N. Sleep , U. Hansen , The bent Hawaiian-Emperor hotspot track: Inheriting the mantle wind. Science 324 , 50 (2009). doi:10.1126/science.1161256 pmid:19342579 Abstract/FREE Full Text 11. C. J. Allègre, The evolution of mantle mixing. Philos. Trans. R. Soc. Lond. A 360 , 2411 (2002). doi:10.1098/rsta.2002.1075 CrossRef Medline Web of Science 12. D. L. Anderson, Geophys. Res. Lett. 27 , 3623 (2000). CrossRef Web of Science 13. S. P. Grand, Mantle shear-wave tomography and the fate of subducted slabs. Philos. Trans. R. Soc. Lond. A 360 , 2475 (2002). doi:10.1098/rsta.2002.1077 Abstract/FREE Full Text 14. C. Li , R. D. van der Hilst , E. R. Engdahl , S. Burdick , A new global model for P wave speed variations in Earth’s mantle. Geochem. Geophys. Geosyst. 9 , Q05018 (2008). doi:10.1029/2007GC001806 CrossRef 15. R. Montelli et al ., Finite-frequency tomography reveals a variety of plumes in the mantle. Science 303 , 338 (2004). doi:10.1126/science.1092485 pmid:14657505 Abstract/FREE Full Text 16. C. J. Wolfe et al ., Mantle shear-wave velocity structure beneath the Hawaiian hot spot. Science 326 , 1388 (2009). doi:10.1126/science.1180165 pmid:19965755 Abstract/FREE Full Text 17. C. J. Wolfe et al ., Mantle P-wave velocity structure beneath the Hawaiian hotspot. Earth Planet. Sci. Lett. 303 , 267 (2011). doi:10.1016/j.epsl.2011.01.004 CrossRef 18. G. Helffrich, Topography of the transition zone seismic discontinuities. Rev. Geophys. 38 , 141 (2000). doi:10.1029/1999RG000060 CrossRef 19. T. Katsura , E. Ito, The system Mg 2 SiO 4 -Fe 2 SiO 4 at high pressures and temperatures: Precise determination of stabilities of olivine, modified spinel, and spinel. J. Geophys. Res. 94 , 15663 (1989). doi:10.1029/JB094iB11p15663 CrossRef 20. X. Li et al ., Mapping the Hawaiian plume conduit with converted seismic waves. Nature 405 , 938 (2000). doi:10.1038/35016054 pmid:10879532 CrossRef Medline 21. J. A. Collins , F. L. Vernon , J. A. Orcutt , R. A. Stephen, Upper mantle structure beneath the Hawaiian swell: Constraints from the ocean seismic network pilot experiment. Geophys. Res. Lett. 29 , 1522 (2002). doi:10.1029/2001GL013302 CrossRef 22. I. Wlbern et al ., Deep origin of the Hawaiian tilted plume conduit derived from receiver functions. Geophys. J. Int. 166 , 767 (2006). doi:10.1111/j.1365-246X.2006.03036.x CrossRef Web of Science 23. Y. Shen , C. J. Wolfe , S. C. Solomon , Seismological evidence for a mid-mantle discontinuity beneath Hawaii and Iceland. Earth Planet. Sci. Lett. 214 , 143 (2003). doi:10.1016/S0012-821X(03)00349-2 CrossRef 24. A. Deuss , S. A. T. Redfern , K. Chambers , J. H. Woodhouse, The nature of the 660-kilometer discontinuity in Earth’s mantle from global seismic observations of PP precursors. Science 311 , 198 (2006). doi:10.1126/science.1120020 pmid:16410518 Abstract/FREE Full Text 25. J. Lawrence , P. M. Shearer, Imaging mantle transition zone thickness with SdS - SS finite-frequency sensitivity kernels. Geophys. J. Int. 174 , 143 (2008). doi:10.1111/j.1365-246X.2007.03673.x CrossRef 26. A. Deuss, Global observations of mantle discontinuities using SS and PP precursors. Surv. Geophys. 30 , 301 (2009). doi:10.1007/s10712-009-9078-y CrossRef 27. C. Houser , Q. Williams, Reconciling Pacific 410 and 660km discontinuity topography, transition zone shear velocity patterns, and mantle phase transitions. Earth Planet. Sci. Lett. 296 , 255 (2010). doi:10.1016/j.epsl.2010.05.006 CrossRef 28. N. Schmerr , E. Garnero , A. McNamara , Deep mantle plumes and convective upwelling beneath the Pacific Ocean. Earth Planet. Sci. Lett. 294 , 143 (2010). doi:10.1016/j.epsl.2010.03.014 CrossRef 29. Materials and Methods are available on Science Online. 30. Q. Cao , P. Wang , R. D. van der Hilst , M. V. de Hoop , S.-H. Shim , Imaging the upper mantle transition zone with a generalized Radon transform of SS precursors. Phys. Earth Planet. Inter. 180 , 80 (2010). doi:10.1016/j.pepi.2010.02.006 CrossRef 31. H. Morishima et al ., The phase boundary between agr- and beta-Mg 2 SiO 4 determined by in situ x-ray observation. Science 265 , 1202 (1994). doi:10.1126/science.265.5176.1202 pmid:17787583 Abstract/FREE Full Text 32. The Clapeyron slope of the wadsleyite to ringwoodite transition is positive ( 42 ) but not well constrained experimentally. 33. T. Irifune et al ., The postspinel phase boundary in Mg2SiO4 determined by in situ X-ray diffraction. Science 279 , 1698 (1998). doi:10.1126/science.279.5357.1698 pmid:9497283 Abstract/FREE Full Text 34. D. J. Weidner , Y. Wang , Chemical- and Clapeyron-induced buoyancy at the 660 km discontinuity. J. Geophys. Res. 103 , (B4), 7431 (1998). doi:10.1029/97JB03511 CrossRef 35. K. Hirose, Phase transitions in pyrolitic mantle around 670-km depth: Implications for upwelling of plumes from the lower mantle. J. Geophys. Res. 107 , (B4), 2078 (2002). doi:10.1029/2001JB000597 CrossRef 36. N. Nishiyama , T. Yagi, Phase relation and mineral chemistry in pyrolite to 2200°C under the lower mantle pressures and implications for dynamics of mantle plumes. J. Geophys. Res. 108 , 2255 (2003). doi:10.1029/2002JB002216 CrossRef 37. M. Akaogi , E. Ito, Calorimetric study on majorite–perovskite transition in the system Mg 4 Si 4 O 12 –Mg 3 Al 2 Si 3 O 12 : Transition boundaries with positive pressure–temperature slopes. Phys. Earth Planet. Inter. 114 , 129 (1999). doi:10.1016/S0031-9201(99)00039-4 CrossRef Web of Science 38. L. Cserepes , D. A. Yuen, On the possibility of a second kind of mantle plume. Earth Planet. Sci. Lett. 183 , 61 (2000). doi:10.1016/S0012-821X(00)00265-X CrossRef Web of Science 39. D. J. DePaolo , E. M. Stolper, Models of Hawaiian volcano growth and plume structure: Implications of results from the Hawaii Scientific Drilling Project. J. Geophys. Res. 101 , (B5), 11643 (1996). doi:10.1029/96JB00070 CrossRef 40. J. Blichert-Toft , F. Albarède , Mixing of isotopic heterogeneities in the Mauna Kea plume conduit. Earth Planet. Sci. Lett. 282 , 190 (2009). doi:10.1016/j.epsl.2009.03.015 CrossRef Web of Science 41. C. G. Farnetani , A. W. Hofmann , Dynamics and internal structure of a lower mantle plume conduit. Earth Planet. Sci. Lett. 282 , 314 (2009). doi:10.1016/j.epsl.2009.03.035 CrossRef Web of Science 42. A. Suzuki et al ., Geophys. Res. Lett. 27 , 803 (2000). CrossRef Web of Science 43. E. R. 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个人分类: 最新论文介绍|7129 次阅读|7 个评论
[转载] Double waterspouts form off Hawaii shore
zuojun 2011-5-4 07:07
By Liz Goodwin Two tall and skinny waterspouts appeared off the south shore of Oahu, Hawaii yesterday, as some of the bad weather that has lately assailed the U.S. mainland has now alighted on the Pacific island. The Star Advertiser reports that the waterspouts appeared during a hail and lightning storm that had reportedly knocked out power for at least 60,000 East Honolulu and Windward Oahuresidents Monday evening. The spouts lasted for about 12 minutes. Waterspouts can become twisters if they reach land, but are usually weak. You can watch the video via the link below: http://news.yahoo.com/s/yblog_thelookout/20110503/us_yblog_thelookout/double-waterspouts-form-off-hawaii-shore
个人分类: Uniquely Hawaii|1467 次阅读|0 个评论
[转载]Radiation (from Japan)? No problem (for Hawaii)
热度 1 zuojun 2011-4-20 02:31
Although some tests continue, state and federal health officials say the tiny amounts found in milk so far are not dangerous By William Cole State health officials are testing large rainwater catchment systems this week on the Big Island, Maui and Kauai for radiation from Japan's nuclear release, but re-emphasized that radiation in milk, rainwater and likely in locally grown produce remains minute. Lynn Nakasone, administrator of the Health Department's Environmental Health Services Division, said produce will not be tested, as other officials noted there is concern about creating a health scare and hurting local farmers. "I know people are thinking, ‘Oh, a little bit (of radiation) here, a little bit there (adds up),' " Nakasone said. "But think of it as calories. What if milk had 0.000004 calories and produce had 0.000003 calories and so on? So you add up all these little calories, but then you probably won't get to even one calorie. "(The radiation from Japan) is kind of like that. We're talking about so minute amounts. Even if you took all the cumulative doses for everything, you are still way below any kind of action level and it's not a health risk at all." http://www.staradvertiser.com/news/hawaiinews/20110419_radiation_no_problem.html
个人分类: News|1453 次阅读|1 个评论
GE tax vs. sales tax
zuojun 2011-3-25 12:03
In the US, two things no one can avoid, death and tax. There are different taxes in the US: federal income tax, state income tax, property tax, and GE tax, among others. Most people in the US know what sales tax is, but if you have ever visited Hawaii you should have noticed that you are taxed for buying a bottle of water at Seven-Eleven (in addition to the bottle fees). So, how many of us who live in Hawaii actually under what GE tax is? I certainly didn’t, until very recently. One day, I was so bored, and typed in “GE tax vs. sales tax.” http://en.wikipedia.org/wiki/Gross_receipts_tax In particular, tax-exempt universities may NOT be exempted from Hawaii’s GE tax (according to http://www.state.hi.us/tax/taxfacts/tf96-01.pdf ). 11. Are tax-exempt organizations exempt from the general excise tax when they buy goods and services? No. Because the general excise tax is levied on the business receiving the income rather than on the customer, businesses are subject to the general excise tax on transactions with tax-exempt organizations because businesses are not tax-exempt even if their customers are. Therefore, tax-exempt organizations will have the general excise tax passed on to them when they buy goods and services. Tax-exempt organizations are only exempt from paying the general excise tax on certain income which they receive.
个人分类: Uniquely Hawaii|2768 次阅读|0 个评论
Shopping online has become norm for people living in Hawaii
zuojun 2011-1-26 04:27
Thinking ahead about my March trip to China, I need a down parka. Finding one in Honolulu is difficult, even if one is willing to pay a bit more. Just as I get ready to go online, a friend at work asked me if I want to keep hers. She ordered it from lendsend.com. http://www.landsend.com/pp/QuiltedDownParka~212712_59.html?bcc=yaction=order_moresku_0=::DX5CM_MERCH=IDX_00007__0000001029 I tried it on, and like it! So, see you in March!
个人分类: Uniquely Hawaii|2296 次阅读|0 个评论
Why I thought Hawaii was a very poor state in the U.S.
zuojun 2010-11-15 10:05
According to Hawaii Foodbank, it provides food to 183,500 different people each year, including 55,000 children. In Hawaii, 1 in 7 people are in need of food assistance. The foodbank is very effective at collecting donations. For example, they print ticket-like coupons of three different face values, and place them at supermarket check-out counters during holiday seasons. When you are purchasing food to feed your loved ones at home, how could you down down a small request, such as $x will provide a child breakfast for a week?
个人分类: Thoughts of Mine|3139 次阅读|0 个评论
Columbus Day, not for the State of Hawaii
zuojun 2010-10-7 05:18
United States observance (from wikipedia) In April 1934, as a result of lobbying by the Knights of Columbus, Congress and President Franklin Delano Roosevelt October 12 was made a federal holiday under the name Columbus Day . Since 1971, the holiday has been fixed to the second Monday in October, coincidentally the same day as Thanksgiving in neighboring Canada (which was fixed to that date in 1959). It is generally observed today by banks, the bond market, the U.S. Postal Service and other federal agencies, most state government offices, and some school districts. Most businesses and some stock exchanges remain open, however some states and municipalities abstain from observing the holiday. That's right, the State of Hawaii does not observe this federal holiday
个人分类: Uniquely Hawaii|3054 次阅读|0 个评论
How to have a great time in Hawaii (2): The Big Island
zuojun 2010-8-24 15:37
If you have never seen a live volcano before, as most Chinese have not, I would recommend you spend a day or two on the Big Island. The Island of Hawai i , also called the Big Island or Hawai i Island, is a volcanic island. If you only have limited time, say one day, you may want to land at the Kona Airport (on the west side of the island), go straight to the Volcanoes National Park , and return your rental car at the Hilo Airport (on the east side of the island, shorter drive). The rental car company may charge you extra $50 for dropping off at a different airport, but its totally worth it. I enjoy the long drive from Kona to the park. (If you really dont have time, then use the Hilo Airport for arrival and departure.) Plan your visit using the NPS website: Hawaii Volcanoes Natioal Park To watch the lava flow at night, you can stay at the Volcano House (closed until 2012), or in a nearby Volcano Village (outside the park where there are quite a few restaurants). There may be closed areas in the park: closed areas On the way from Kona to the Volcanoes Park, stop by the South Point , which is the southernmost point in the United States. You also dont want to miss the Punaluu Beach (also called Black Sand Beach), where you may see Green_turtles . There was a hot pond nearby, but I cannot remember its location without looking hard on a detailed map. If you have more time, instead of returning your rental car in Hilo, you drive from Hilo to the Mauna Kea Observatory off Route 200. Then through Waimea Valley in the northwest, you reach the west coast again and drive south to Kona. On the way, you may stop for a wonderful sunset.Getting to the observatory is not easy. I thought that I was well prepared, with a 4-wheel-drive jeep, but I didnt make it. Mauna Kea is the tallest, though not the highest, mountain in the world. This is because a significant part of the mountain is underwater. If Mauna Kea is measured from its oceanic base, it is over 10,000m (33,000 ft), significantly taller than Mount Everest , the highest peak above sea level.
个人分类: Uniquely Hawaii|3574 次阅读|2 个评论
[转载] Hawaii is a paradise, and I am only a visitor here...
zuojun 2010-8-4 14:08
Sovereignty movement survives and thrives By Jonathan Osorio Why should the needs, actions, responses and ultimately the fate of Native Hawaiians concern the residents of this state? Why should Hawaiians not simply be treated as any other failed or failing minority in the United States? Increasingly we believe we should govern ourselves, and why shouldn't we? Ninety years of the Hawaiian Homes Act and 30 years of OHA seem only to demonstrate that neither the U.S. nor the state of Hawaii can provide homes and work, education and a national and cultural pride that matches what our own kingdom provided in the 19th century. And besides, this is our country, isn't it? Even people who claim that the kingdom's property is now America's property can scarcely deny that a vocal and active sovereignty and independence movement thrives among our people today. ULTIMATELY, the call for a just solution to the Hawaiian national claims may need to be framed not simply as the pursuit of social justice and redress for the American theft of the Hawaiian nation and its lands, but as a self-interested and rational acknowledgment that native Hawaiians are struggling to succeed, to live as Hawaiians, not Americans, despite all that has been done to them. Whether a peaceful and mutually satisfying arrangement can be made between the native people and everyone else living in Hawaii could depend on how much of a struggle we are forced to endure. And remember, none of us are going anywhere. Jonathan Kay Kamakawiwoole Osorio is a professor of Hawaiian studies at the University of Hawaii at Manoa, and an advocate for the restoration of Hawaii's political independence. p.s. Enjoy the comments of this article, too.
个人分类: Uniquely Hawaii|2650 次阅读|0 个评论
Only in Hawaii: policemen are nice
zuojun 2010-7-24 07:17
A re-retired co-worker came to town to have dim sum with us. We went in her car, and took an on-street parking that has one-hour limit. Good time went by fast. As we walked towards her parked car, a uniformed police woman was looking at the parking meter for her car We waved to the police, and she waved back, gesturing: Is this your car? We all nodded from a distance, and she walked away without giving us a ticket for expired meter. This is not the first time I have encountered a nice police(wo)man in Honolulu. As we say here, Lucky, we live in Hawaii!
个人分类: Uniquely Hawaii|2992 次阅读|1 个评论
May Day is Lei Day in Hawaii (updated with photos)
zuojun 2010-4-28 09:20
If you happen to be in Hawaii, don't miss the Lei Day celebration To learn more, go to http://www.honolulu.gov/parks/programs/leiday/photogallery.htm This is the line for lei viewing... ... in the humid afternoon of Lei Day, 2010. I guess I will go people watching this year... There are two chains. People waiting in line will have a close look at the display; people walking by have to stay behind the outer chain, like me (too lazy to wait in line). Lei on a hat (the first three places). Winners of this year's Theme lei. I want this lei! The staff is curious enough to take a picture of this unique lei (purple and white). Thank you for keeping us pretty a little longer in this humid afternoon... Ladies in pretty hats: Dr. Berman in green, and her friend. This three-year-old girl is very camera friendly. The END
个人分类: Uniquely Hawaii|5032 次阅读|1 个评论
Introducing Aloha Shirt
zuojun 2010-4-18 03:49
This is the perfect time to introduce Aloha shirt , because in November 2009, President Obama selected his home state of Hawaii as the site of the main APEC 2011 meetings. What do I know about Aloha shirt ? Actually a lot, since I have lived in Hawaii for nearly 10 years. On the other hand, why bother to write something where there is a good piece to steal from the Net? I know wikipedia sometimes is not accurate, but this one on Aloha_shirt is better than anything I can put together. So I will just underline the parts I think are the most important: The Aloha shirt is a style of dress shirt originating in Hawaii . It is currently the premier textile export of the Hawaii manufacturing industry. The shirts are printed, mostly short-sleeved, and collared. They usually have buttons, sometimes as a complete button-down shirt, and sometimes just down to the chest (pullover). Aloha shirts usually have a left chest pocket sewn in to make the printed pattern continuous. Aloha shirts may be worn by men or women; women's aloha shirts usually have a lower-cut, v-neck style. The lower hem is straight, as the shirts are not meant to be tucked in. Aloha shirts exported to the mainland United States and elsewhere are called Hawaiian shirts and often brilliantly colored with floral patterns or generic Polynesian motifs and are worn as casual, informal wear. Traditional men's aloha shirts manufactured for local Hawaiian residents are usually adorned with traditional Hawaiian quilt designs, tapa designs, and simple floral patterns in more muted colors. Contemporary aloha shirts may have prints that do not feature any traditional Hawaiian quilt or floral designs and instead may have such elements as automobiles, drinks, sports team logos, or other elements arranged in the same pattern as a traditional aloha shirt. Aloha shirts manufactured for local consumption are considered formal wear in business and government , and thus are regarded as equivalent to a shirt, coat, and tie (generally impractical in the warmer climate of Hawaii) in all but the most formal of settings. These shirts often are printed on the interior, resulting in the muted color on the exterior, and are called reverse print; this is often mistaken for the shirt being worn inside-out . If you want the best Aloha shirt , go for Tori Richard or Reyn's.
个人分类: Uniquely Hawaii|3849 次阅读|0 个评论
Why is Hawaii the site for the main APEC 2011 meetings?
zuojun 2010-4-18 03:19
Obviously, its one of the Obama Effects. APEC, or the Asia Pacific Economic Cooperation, is the premier forum for Asia-Pacific economies to cooperate on regional trade and investment issues. APECs annual meetings are hosted each year by a different member economy, and 2011 marks the first time since the first meeting convened on Blake Island, Wash., in 1993 that the United States is serving as the host. In November, President Obama selected his home state of Hawaii as the site of the main APEC 2011 meetings. To learn more, go to http://www.hawaii.edu/news/article.php?aId=3535
个人分类: Uniquely Hawaii|3509 次阅读|0 个评论
So cold today (on April 16, 2010 in Honolulu)
zuojun 2010-4-17 09:09
It's 73F (23C) at 3:00 pm in my living room, the coldest temperature I have ever noticed since Christmas 2008 (unless the digital clock is sick). It's overcast, with low clouds, outside.
个人分类: Uniquely Hawaii|3377 次阅读|0 个评论
How to have a great time in Hawaii (1): Oahu (revised)
zuojun 2010-3-31 16:12
Most people think Honolulu equals Hawaii. Well, Honolulu is a city and county on Oahu, one of the main islands in Hawaii. Here is a list I put together for someone who can only afford x day(s) on Oahu, where x=1, 2, …, N. Day 1: Pearl Harbor (get there early and expect to spend 3-4 hours for the entire free tour, which includes a movie, a boat ride to and from the USS Arizona Memorial --you can now reserve your tickets online), Pali Lookout (a place for the final battle that united the Hawaii Islands), and an evening at the Waikiki Beach. Day 2: Diamond Head (an easy hike of 2 hours up and back), ocean side of the Diamond Head (a surfing site), Hanauma Bay (not going down to snorkel), Blow Hole, Valley of the Temples (General ZHANG, Xueliang’s resting place), and an evening at the Aloha Tower. Day 3: Hanauma Bay (snorkeling). Make sure you go to the far LEFT of the bay, where you will see lots of fish, and even big green turtles if you are as lucky as I was. Day 4: Chinaman Hat, and North Shore. Day 5: Leeward Coast, all the way to the Kaena Point (the final stretch cannot be reached by car, so you need to hike for 2-3 hours to complete the trip or not). Day 6: Windward Coast, Kailua Beach (where Obama’s family vacations each Christmas time). I will stop here, since most people cannot afford more than six days on one small island. All these places you can read about using google. What is not given here is where to eat GOOD food. Ask me before you start your trip, and I will make sure you don’t just eat junk food in paradise! ps. The newly opened International Market Place is very nice (though no longer inexpensive).
个人分类: Most shared|3889 次阅读|0 个评论
A vary cold spring in Hawaii
zuojun 2010-3-21 05:14
I know I should not complain no matter how cold or hot it gets in Hawaii. This morning, the temperature in my living room (on 12th floor) is 73F (about 23C), the coldest since I got this digital clock with temperature reading as a Christmas gift in 2008. Even if this is part of the global cooling, we should still be concerned about CO2 emission because of ocean acidification. ps. I didn't know Today is the first day of spring in the Northern Hemisphere. when I wrote my Blog. It is no guarantee of spring-like weather, but officially the season's start comes around at the same time each year nonetheless. Well, sort of... To read more, go to: Why spring starts today
个人分类: Uniquely Hawaii|3342 次阅读|1 个评论
Celebrating the Year of Tiger in Hawaii
zuojun 2010-2-15 08:11
I have always taken Chinese New Year seriously because I have pure Chinese blood Celebrating Chinese New Year in U.S. may be difficult because the Chinese New Years Day does not always fall on a weekend. This is my lucky year for many reasons. First of all, the Chinese New Year is on Sunday. Second, this weekend happens to be a long (three-day) weekend. Third, I managed to submit a proposal just before the weekend. I was ready to party! I wanted to take full advantage of the long weekend, so I contacted some old and new friends and made arrangements for each of the three days! On Saturday, I met my old friend, Jenny, for lunch. Our sons used to attend Chinese school together. Now both young men are juniors, so we had a lot to chat about SAT and college. For dinner, I didnt want to cook too much, but I wanted it to be authentic Chinese meal, fit for Chinese New Years Eve. I decided to make a dish that can be enjoyed without having additional rice (which would be too ordinary). The dish is called Pearl meat balls. It can be any kind of meat balls, but roll each ball over pre-soaked mochi (sweet) rice before putting them on a plate. Steam the meat balls for 20-25 minutes, making sure the water was sufficient. (I did smell some burning doing the second batch, because I didnt add enough water.) Since I dont like too much meat, my version of meat balls is always half-and-half: half meat and half medium-firm tofu, with finely chopped ginger roots, green onions, pre-soaked dried mushroom and canned water chestnuts. They taste even better with some chill sauces. I know it does not sound much for people living in China, but it was a good effort on my part, from shopping for the ingredients to serving. Sunday was supposed to be easy, since I made a reservation for three families to have dinner at the Chins. We have been celebrating Chinese New Year for many years now. Here is the menu for tonights dinner: 1) Crispy chicken (whole) 2) Green tea smoked duck (half) 3) Walnut shrimp without mayonnaise 4) Salt and peppered shrimp 5) Beef with broccoli (keep it for Ali) 6) Sizzling filet of beef with black pepper sauce 7) Chinese broccoli with dry baby fish 8) Ma Po tofu 9) Assorted pan fried crispy noodle Instead, I worked hard on Sunday, too. I was doing a little cleaning in the kitchen, when the young master gently asked for home-made crepe. We called it egg-pancake, which was made by my beloved grandma when we were young, using eggs, milk (or water), flour, and sugar (or green onion and salt). The time-consuming part is to prepare the batter. I had not made crepes for a long time, but granted his wish, because its a special day. Tomorrow will be exciting, because I am to meet three other moms for lunch, two of them I never met. As a parent, I realized long ago that I dont always get to choose my friends any more. There were times that two moms got along very well, but the two kids did not. This time, I am meeting these moms because their sons are my sons friends. It should be fun!
个人分类: Uniquely Hawaii|3527 次阅读|1 个评论

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