Surface subsidence caused by mantle plumes and volcanic loading in large igneous provinces
Surface subsidence caused by mantle plumes and volcanic loading in large igneous provinces
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DOI：
10.1016/j.epsl.2010.01.015
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发表时间：
2010-03-01
影响因子：
5.3
通讯作者：
Zhong, Shijie
中科院分区：
文献类型：
--
作者：
Leng, Wei;Zhong, Shijie
数百万年内，大量的洪水玄武岩在一个大区域内爆发，形成了大的火成岩省。它们形成的一个流行模型是地幔柱模型，其中地幔柱头起源于核幔边界，通过地幔上升，并产生地形隆起，最终在地表大规模熔融。然而，许多地质观测表明，在中部地区的表面沉降之前或期间的洪水玄武岩喷发。在这项研究中，我们表明，羽头暂时积水低于660公里的相变边界引起显着的沉降在地球表面在火山爆发前的一段时间内，并从喷发玄武岩的负荷引起表面沉降在周边的喷发区，影响环境的玄武岩喷发的后续情节。因此，我们的研究表明，所观察到的沉降历史，在许多洪水玄武岩省的地幔柱的动力学特征，并可用于诊断确定地幔柱引起的洪水玄武岩事件。(c)2010 Elsevier B.V.保留所有权利。
Large igneous provinces form with massive flood basalts being erupted over a large region within a few million years. A prevailing model for their formation is a mantle plume model in which a plume head originates from the core-mantle boundary, ascends through the mantle, and produces topographic uplift and eventually massive melting at the surface. However, many geological observations indicate surface subsidence in the central region before or during flood basalt eruptions. In this study, we demonstrate that a plume head temporarily ponding below the 660-km phase change boundary causes significant subsidence at the Earth's surface over an extended period before the eruption, and that the loading from erupted basalts causes surface subsidence at the periphery of the eruption area that affects the environment for subsequent episodes of basalt eruptions. Our studies therefore demonstrate that the observed subsidence history in many flood basalt provinces is characteristic of the dynamics of mantle plumes and may be used as diagnostics for identifying plume-induced flood basalt events. (c) 2010 Elsevier B.V. All rights reserved.