The Manihiki Plateau—A multistage volcanic emplacement history
The Manihiki Plateau—A multistage volcanic emplacement history
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马尼希基高原——多阶段火山侵位历史
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
G. Uenzelmann‐Neben
中科院分区：
文献类型：
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作者：
R. Pietsch;G. Uenzelmann‐Neben
马尼希基高原是一个大火成岩省，其形成历史尚不清楚。新的高分辨率地震反射数据横跨高高原，马尼希基高原最大的建筑物，提供了多阶段岩浆侵位的证据。改进的数据质量允许识别更早的火山阶段，初始形成阶段（>125 Ma），以及先前已知的火山形成阶段：膨胀阶段（125-116），以前称为主阶段和次级火山阶段（100-65 Ma）。这有助于加深对布设情况的了解。一个基底内反射带IB 1揭示了初始火山形成的结束，并形成了高原的核。这一特征表明，它继续超越了马尼希基陡坎，从而支持了马尼希基高原在最初形成和扩张阶段向东延伸的假设。扩张阶段的特点是大量的火山喷发，使整个高原和邻近的西部高原的基底变平和延伸，相反，这表明了大规模的构造蚀变。次级火山作用阶段（结束于65 Ma）形成的挤压中心主要集中于沿着高原边缘，表明岩浆源区已从与高原初始侵位和扩张阶段有关的岩浆源区转移到构造蚀变边缘的诱发火山作用。
The formation history of the Manihiki Plateau, a Large Igneous Province, is poorly understood. New high‐resolution seismic reflection data across the High Plateau, the largest edifice of the Manihiki Plateau, provide evidence for multistage magmatic emplacement. Improved data quality allows for an identification of an earlier volcanic phase, the initial formation phase (>125 Ma), in addition to the previously known volcanic formation phases: the expansion phase (125–116) formerly called main‐phase, and the secondary volcanic phase (100–65 Ma). This enhances the understanding of the emplacement scenario. An intrabasement reflection band IB1 reveals the end of initial volcanic formation and forms the nucleus of the High Plateau. This feature provides indications that it continued beyond the Manihiki Scarp and thus supports the hypothesis of an extension of the Manihiki Plateau to the East during the initial formation and expansion phases. The expansion phase is characterized by massive volcanic outpourings leveling and extending the basement throughout the High Plateau and the neighboring Western Plateaus, which in contrast shows massive tectonic alteration. Extrusion centers formed within the secondary volcanic phase (ending ∼65 Ma) are mainly concentrated along the margins of the High Plateau, suggesting the magmatic sources shifted from those being related to the initial emplacement and expansion phases of the High Plateau to induced volcanism at the tectonically altered margins.
影响因子：
5
作者：
Hoernle, Kaj;Hauff, Folkmar;Davy, Bryan
通讯作者：
Davy, Bryan