Seismic structure and magmatic construction of crust at the   ultraslow-spreading Southwest Indian Ridge at 50 degrees 28 &apos; E

doi:10.1002/2016JB013377

CORC > 北京大学 > 地球与空间科学学院

	Seismic structure and magmatic construction of crust at the ultraslow-spreading Southwest Indian Ridge at 50 degrees 28 ' E
	Jian, Hanchao ; Chen, Yongshun John ; Singh, Satish C. ; Li, Jiabiao ; Zhao, Minghui ; Ruan, Aiguo ; Qiu, Xuelin
刊名	JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
	2017
关键词	MID-ATLANTIC RIDGE EAST PACIFIC RISE TRAVEL-TIME DATA DE-FUCA RIDGE AXIS HYDROTHERMAL FLOW OCEANIC-CRUST SEA-FLOOR ENDEAVOR SEGMENT NUMERICAL-MODELS MIDOCEAN RIDGES
DOI	10.1002/2016JB013377
英文摘要	We present a three-dimensional crustal structure of a magmatically robust segment of the ultraslow- spreading Southwest Indian Ridge at 50 degrees 28' E based on tomographic inversions of an ocean bottom seismometer data set. Our results show an upper crustal low-velocity band in the axial zone, which is attributed to increased porosities due to active extensions, leading to anisotropy in the upper crust with a fast direction subperpendicular to the spreading direction. In the lower crust, the results reveal a round-shaped low-velocity anomaly at the segment center, indicative of high temperatures and/or a small amount of melt, suggestive of the presence of an axial magma chamber. At the midcrustal depth, an along-axis asymmetry is observed with respect to the segment center. While a small low-velocity anomaly indicates lateral magma redistribution toward the western segment end, the deep-penetrating low velocities and high velocity gradients toward the eastern end suggest that the crust is colder and contains a thicker fractured layer. This asymmetry occurs very close to the axial magma chamber (< 5 km) and seems to be related to the fact that the oblique-spreading domain at the eastern end offsets the ridge axis by a larger distance than that at the western end. We suggest that an along-axis deep-penetrating hydrothermal circulation develops on the east side of the axial magma chamber, in response to the rapid change from orthogonal-to oblique-spreading domains and cools the crust.; MOST grant [2012CB417301]; COMRA grant [DYXM-115-02-3-01]; NSF China grant [41030857]; SCI(E); ARTICLE; 1; 18-42; 122
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/476329]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Jian, Hanchao,Chen, Yongshun John,Singh, Satish C.,et al. Seismic structure and magmatic construction of crust at the ultraslow-spreading Southwest Indian Ridge at 50 degrees 28 ' E[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,2017.
APA	Jian, Hanchao.,Chen, Yongshun John.,Singh, Satish C..,Li, Jiabiao.,Zhao, Minghui.,...&Qiu, Xuelin.(2017).Seismic structure and magmatic construction of crust at the ultraslow-spreading Southwest Indian Ridge at 50 degrees 28 ' E.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH.
MLA	Jian, Hanchao,et al."Seismic structure and magmatic construction of crust at the ultraslow-spreading Southwest Indian Ridge at 50 degrees 28 ' E".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH (2017).