| 1 | Testing the mantle plume hypothesis: an IODP effort to drill into the Kamchatka-Okhotsk Sea basement显示文摘The great mantle plume debate(GPD) has been going on for ~15 years(Foulger and Natland, 2003;Anderson, 2004; Niu, 2005; Davies, 2005; Foulger, 2005; Campbell, 2005; Campbell and Davies, 2006),centered on whether mantle plumes exist as a result of Earth's cooling or whether their existence is purely required for convenience in explaining certain Earth phenomena(Niu, 2005). Despite the mounting evidence that many of the so-called plumes may be localized melting anomalies, the debate is likely to continue. We recognize that the slow progress of the debate results from communication difficulties.Many debaters may not truly appreciate(1) what the mantle plume hypothesis actually is, and(2) none of the petrological, geochemical and geophysical methods widely used can actually provide smoking-gun evidence for or against mantle plume hypothesis. In this short paper, we clarify these issues, and elaborate a geologically effective approach to test the hypothesis. According to the mantle plume hypothesis, a thermal mantle plume must originate from the thermal boundary layer at the core-mantle boundary(CMB), and a large mantle plume head is required to carry the material from the deep mantle to the surface. The plume head product in ocean basins is the oceanic plateau, which is a lithospheric terrane that is large(1000's km across), thick(>200 km), shallow(2–4 km high above the surrounding seafloors), buoyant(~1% less dense than the surrounding lithosphere), and thus must be preserved in the surface geology(Niu et al., 2003). The Hawaiian volcanism has been considered as the surface expression of a type mantle plume, but it does not seem to have a(known) plume head product. If this is true, the Hawaiian mantle plume in particular and the mantle plume hypothesis in general must be questioned. Therefore, whether there is an oceanic plateau-like product for the Hawaiian volcanism is key to testing the mantle plume hypothesis, and the Kamchatka-Okhotsk Sea basement is the best candidate to find out if it is indeed the Hawaiian mantle plume head product or not(Niu et al., 2003; Niu, 2004). | Yaoling Niu Xuefa Shi Tiegang Li Shiguo Wu Weidong Sun Rixiang Zhu | 2017 | Science Bulletin2017，62，21： | 8 |
| 2 | 有限频与射线层析成像比较研究综述显示文摘从正演近似性和反演多解性两方面对有限频与射线理论的争论历史和比较研究进展进行介绍并评述.从早期的衍射层析成像开始,回顾了有限频理论的发展历史.详细介绍了2005至2006年间有限频理论的拥护者与质疑者之间的一场影响深远的争论.这场争论纠正了之前十多年许多地震学家将地震波相关走时与初至走时相混淆的错误认识,使有限频理论得到广泛认可,但有限频层析成像的实际分辨能力是否强于射线层析成像分歧很大.争论之后,有限频与射线层析成像比较研究成为一个研究方向.在体波领域,正演理论和实际反演的比较研究显示出两者有明显的差别,而合成反演实验因计算量问题没有取得突破性进展.在面波领域,正演理论、实际反演和合成反演实验都有深入的比较研究,显示两者的差别不是很大. | 江燕 陈晓非 | 2011 | 地球物理学进展2011，26，5： | 8 |
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