Evidence for anomalous mantle upwelling beneath the Arabian Platform from travel time tomography inversion
Evidence for anomalous mantle upwelling beneath the Arabian Platform from travel time tomography inversion
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DOI：
10.1016/j.tecto.2015.11.022
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发表时间：
2016-01-23
期刊：
影响因子：
2.9
通讯作者：
Bushenkova, Natalia
中科院分区：
文献类型：
--
作者：
Koulakov, Ivan;Burov, Evgeniy;Bushenkova, Natalia
我们提出了阿拉伯半岛、红海及周边地区下上地幔 P 速度异常的新模型。该模型是利用国际地震中心（ISC）全球目录中 1980-2011 年的走时数据计算得出的。通过多项综合测试来测试模型的可靠性。在由此产生的地震模型中，红海显然与上地幔中至少 300 公里深度的较高 P 速度异常相关。这种异常可能是由于被动裂谷导致岩石圈扩展和变薄导致主要地幔界面向上偏移造成的。阿拉伯地台的厚岩石圈被成像为深达 200-250 公里的高速异常。在该板块下方，我们观察到一个低速结构，该结构被解释为热地幔上升流。根据断层扫描结果，我们认为这种上地幔异常可能代表了向西迁移的热物质，并在阿拉伯西部新生代玄武岩熔岩田的形成中发挥了重要作用。在阿拉伯板块的东北侧，我们清楚地观察到扎格罗斯和莫克兰下方有一个倾斜的高速带，这被解释为阿拉伯板块岩石圈俯冲或分层的痕迹。 (C) 2015 Elsevier B.V. 保留所有权利。
We present a new model of P-velocity anomalies in the upper mantle beneath the Arabian Peninsula, Red Sea, and surrounding regions. This model was computed with the use of travel time data from the global catalogue of the International Seismological Center (ISC) for the years of 1980-2011. The reliability of the model was tested with several synthetic tests. In the resulting seismic model, the Red Sea is clearly associated with a higher P-velocity anomaly in the upper mantle at least down to 300 km depth. This anomaly might be caused by upward deviation of the main mantle interfaces caused by extension and thinning of the lithosphere due to passive rifting. Thick lithosphere of the Arabian Platform is imaged as a high-velocity anomaly down to 200-250 km depth. Below this plate, we observe a low-velocity structure that is interpreted as a hot mantle upwelling. Based on the tomography results, we propose that this upper mantle anomaly may represent hot material that migrates westward and play a major role in the formation of Cenozoic basaltic lava fields in western Arabia. On the northeastern side of the Arabian Plate, we clearly observe a dipping high-velocity zone beneath Zagros and Makran, which is interpreted as a trace of subduction or delamination of the Arabian Plate lithosphere. (C) 2015 Elsevier B.V. All rights reserved.