Variable thermal loading and flexural uplift along the Transantarctic Mountains, Antarctica
Variable thermal loading and flexural uplift along the Transantarctic Mountains, Antarctica
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DOI：
10.1130/g38784.1
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发表时间：
2017-05-01
期刊：
影响因子：
5.8
通讯作者：
Park, Yongcheol
中科院分区：
文献类型：
--
作者：
Brenn, Gregory R.;Hansen, Samantha E.;Park, Yongcheol
跨南极山脉（TAMs）的高海拔被认为是弯曲的起源，但到目前为止，对隆起的热贡献尚未被量化。在这里，我们提出了新的P-和S-波层析成像图像的上地幔地震结构下的中央到北方TAMs，这揭示了两个，集中的低速异常罗斯岛和特拉诺瓦湾下横向延伸的TAMs前下方，并连接一个低速区约束近海内的维多利亚陆地盆地。集中的低速度被解释为部分熔融的浅区域，由与沿着恐怖裂谷的新生代伸展相关的缓慢（温暖）上地幔的广泛区域连接。我们的层析成像结果的基础上的热负荷约束被用来更新TAMs的弯曲隆起模型。我们的研究结果证实，热浮力是一个主要组成部分，导致的TAMs的隆起，但建议的热负荷是可变的沿着TAMs前。
The high elevations of the Transantarctic Mountains (TAMs) have been suggested to be flexural in origin, but to date, the thermal contribution to uplift has yet to be quantified. Here, we present new P- and S-wave tomography images of the upper-mantle seismic structure beneath the central to northern TAMs, which reveal two, focused low-velocity anomalies beneath Ross Island and Terra Nova Bay that laterally extend beneath the TAMs front and that are connected by a low-velocity region constrained offshore within the Victoria Land Basin. The focused low velocities are interpreted as shallow regions of partial melt, connected by a broad region of slow (warm) upper mantle associated with Cenozoic extension along the Terror Rift. Thermal loading constraints based on our tomographic results are used to update flexural uplift models for the TAMs. Our findings confirm that thermal buoyancy is a principal component leading to the uplift of the TAMs but suggest that the thermal loading is variable along the TAMs front.