Geochemistry of the NW Pacific Plate: Origins of Indian and Pacific Mantles and Nature of Their Boundary: ─インド洋太平洋型マントルの成因とマントル境界の特性─
Geochemistry of the NW Pacific Plate: Origins of Indian and Pacific Mantles and Nature of Their Boundary: ─インド洋太平洋型マントルの成因とマントル境界の特性─
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西北太平洋板块的地球化学：印度洋和太平洋地幔的起源及其边界的性质： ─ 印度洋-太平洋地幔的起源和地幔边界的特征 ─
DOI：
10.5026/jgeography.126.163
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发表时间：
2017
影响因子：
3.1
通讯作者：
R. Senda
中科院分区：
文献类型：
--
作者：
J. Kimura;T. Miyazaki;Q. Chang;B. Vaglarov;R. Senda
利用Pb - Nd - Hf同位素研究了太平洋板块海洋地壳的源地幔，并与全球海洋玄武岩同位素数据库进行了比较。整个太平洋板块的东半部，由沿东太平洋隆起和胡安·德·富卡山脊的同位素不同的太平洋地幔形成，大部分仍在海底。相反，太平洋板块的西半部向西变得更年轻，被认为是由伊扎那吉太平洋脊（IPR）形成的。在70 ~ 65 Ma沿千岛-日本-南开-琉球（KJNR）海沟俯冲，目前形成太平洋板块前缘，停滞在中国下方的地幔过渡带。俯冲的地壳构造是由太平洋和印度地幔形成的。西太平洋165 ~ 130 Ma钻孔岩心的玄武岩同位素组成表明其为太平洋地幔成因。然而，沿KJNR海沟的吸积棱镜中刮出的海底玄武岩（80 Ma）具有印度地幔特征。这表明：(1)起源为IPR的较年轻西太平洋板块是由印度地幔形成的；(2)至少自白垩纪以来，印度-太平洋地幔边界在西太平洋是静止的；(3)IPR越过了该边界。印度地幔被认为是由一个枯竭的MORB源地幔（DMM）形成的，这是由于一个古老的熔体枯竭事件（2 - 3 Ga）和随后的同位素增长以及与次大陆岩石圈地幔的混合。相比之下，太平洋地幔起源于3 - 1.5 Ga的原始地幔，随后仅发生同位素增长。这些不同的形成过程可能与超大陆和超海洋的形成有关，其中印度地幔形成于次大陆环境，而太平洋地幔形成于洋脊环境。
The source mantle of the ocean crust on the Pacific Plate is examined using Pb⊖Nd⊖Hf isotopes and compared to a global isotope database of ocean basalts. The entire eastern half of the Pacific Plate, formed from an isotopically distinct Pacific mantle along the East Pacific Rise and the Juan de Fuca Ridge, largely remains on the seafloor. Conversely, the western half of the Pacific Plate becomes younger westward and is thought to have formed from the Izanagi⊖Pacific Ridge (IPR). The ridge subducted along the Kurile⊖Japan⊖Nankai⊖Ryukyu (KJNR) Trench at 70⊖65 Ma and currently forms the leading edge of the Pacific Plate stagnated in the mantle transition zone beneath China. The subducted IP formed from both Pacific and Indian mantles. Isotopic compositions of the basalts from borehole cores of 165⊖130 Ma in the western Pacific show that these are of Pacific mantle origin. However, the scraped-off ocean floor basalts (80⊖70 Ma) in the accretionary prism along the KJNR Trench have Indian mantle signatures. This indicates: (1) the younger western Pacific Plate of IPR origin formed from the Indian mantle, (2) the Indian⊖Pacific mantle boundary has been stationary in the western Pacific at least since the Cretaceous, and (3) the IPR moved over the boundary. The Indian mantle is thought to have formed from a depleted MORB source mantle (DMM) due to an ancient melt depletion event (2⊖3 Ga) and subsequent isotopic growth and mixing with a sub-continental lithospheric mantle. In contrast, the Pacific mantle originated from a primitive mantle at 3⊖1.5 Ga followed by isotopic growth alone. These different formation processes may relate to the formation of the supercontinent and superocean where the Indian mantle was formed in a sub-continental environment whereas the Pacific mantle formed in an oceanic ridge environment.
影响因子：
2.9
作者：
M. Flower;R. Russo;K. Tamaki;N. Hoàng
通讯作者：
M. Flower;R. Russo;K. Tamaki;N. Hoàng
影响因子：
5.2
作者：
M. Seton;N. Flament;J. Whittaker;R. Müller;M. Gurnis;D. Bower
通讯作者：
M. Seton;N. Flament;J. Whittaker;R. Müller;M. Gurnis;D. Bower
DOI：
--
发表时间：
2005
期刊：
Journal of Geophysical Research 110
影响因子：
--
作者：
Matsukage;K.N.;Y.Nishihara;S.Karato
通讯作者：
S.Karato