Lithospheric Erosion in the Patagonian Slab Window, and Implications for Glacial Isostasy
Lithospheric Erosion in the Patagonian Slab Window, and Implications for Glacial Isostasy
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DOI：
10.1029/2021gl096863
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发表时间：
2022-01
影响因子：
5.2
通讯作者：
H. Mark;D. Wiens;E. Ivins;A. Richter;W. Ben Mansour;M. Magnani;E. Marderwald;Rodrigo Adaros;S. Barrientos
中科院分区：
文献类型：
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作者：
H. Mark;D. Wiens;E. Ivins;A. Richter;W. Ben Mansour;M. Magnani;E. Marderwald;Rodrigo Adaros;S. Barrientos
巴塔哥尼亚板块窗口已被提出，以提高固体地球的冰质量负荷变化的覆盖北方和南部巴塔哥尼亚冰原（NPI和SPI，分别）。在这里，我们提出了第一个区域地震速度模型，覆盖了板窗的整个南北范围。上地幔的低速异常表明地幔温度较暖，粘度较低，可能部分熔融。莫霍面下方的低速表明，岩石圈地幔已被热侵蚀的最年轻的部分板片窗口。异常最慢的部分在49°S以北，这意味着NPI和北方SPI覆盖的地幔粘度比南方SPI低。板窗的这一全面地震测绘提供了关键证据，支持先前假设的小冰期后人为冰量损失与快速大地测量观测到的冰川均衡抬升（≥4 cm/年）之间的联系。
The Patagonian slab window has been proposed to enhance the solid Earth response to ice mass load changes in the overlying Northern and Southern Patagonian Icefields (NPI and SPI, respectively). Here, we present the first regional seismic velocity model covering the entire north‐south extent of the slab window. A slow velocity anomaly in the uppermost mantle indicates warm mantle temperature, low viscosity, and possibly partial melt. Low velocities just below the Moho suggest that the lithospheric mantle has been thermally eroded over the youngest part of the slab window. The slowest part of the anomaly is north of 49°S, implying that the NPI and the northern SPI overlie lower viscosity mantle than the southern SPI. This comprehensive seismic mapping of the slab window provides key evidence supporting the previously hypothesized connection between post‐Little Ice Age anthropogenic ice mass loss and rapid geodetically observed glacial isostatic uplift (≥4 cm/yr).