Using Ambient Noise to Image the Northern East African Rift
Using Ambient Noise to Image the Northern East African Rift
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DOI：
10.1029/2018gc008129
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发表时间：
2019-04-01
影响因子：
3.5
通讯作者：
Rychert, Catherine A.
中科院分区：
文献类型：
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作者：
Chambers, Emma L.;Harmon, Nicholas;Rychert, Catherine A.
北方东非大裂谷是一个独特的位置，我们在这里观察到埃塞俄比亚大裂谷的大陆裂谷向阿法尔的初始海底扩张过渡。在这里，我们提出了一个三维的绝对剪切波速度模型的地壳和上地幔的北方大陆从环境噪声层析成像。我们从170个台站（目前超过12年）中生成了4，820个台站对相关函数，这些函数被反演为8-33 s周期的相速度，最后反演为60 km深度的三维绝对剪切速度结构。在最上层地幔的任何地方，剪切速度都比地幔橄榄岩成分的预期要慢（
The northern East African Rift (EAR) is a unique location where we observe continental rifting in the Main Ethiopian Rift (MER) transitioning to incipient seafloor spreading in Afar. Here we present a 3-D absolute shear wave velocity model of the crust and uppermost mantle of the northern EAR generated from ambient noise tomography. We generate 4,820 station pair correlation functions, from 170 stations (present over 12 years), which were inverted for phase velocity from 8-33 s period and finally for 3-D absolute shear velocity structure to 60-km depth. Everywhere in the uppermost mantle, shear velocity is slower than expected for a mantle peridotite composition (