Moho Depths of Antarctica: Comparison of Seismic, Gravity, and Isostatic Results
Moho Depths of Antarctica: Comparison of Seismic, Gravity, and Isostatic Results
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南极洲莫霍面深度：地震、重力和等静压结果的比较
DOI：
10.1029/2018gc008111
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发表时间：
2019
期刊：
影响因子：
3.7
通讯作者：
["F. Pappa
中科院分区：
文献类型：
--
作者：
["F. Pappa
南极洲的岩石圈结构仍未得到充分勘探。在多个地区，包括横贯南极山脉的内陆地区，莫霍面深度估算研究存在超过10千米的差异。考虑到地震台站的稀少以及位场方法的非唯一性，本文基于卫星重力数据并结合现有的受地震约束的莫霍面深度估算值进行了莫霍面深度反演。我们的结果证实，东南极洲下方莫霍面处的密度反差比西南极洲下方要小。将我们反演得到的莫霍面深度与艾里均衡莫霍面模型进行比较，还揭示了东南极洲不同区域下方岩石圈地幔浮力贡献在空间上的变化。最后，为了检验横贯南极山脉 - 威尔克斯冰下盆地系统不同莫霍面深度情景的合理性，我们沿着横贯南极山脉地震实验/甘布尔采夫山脉地震实验地震剖面给出了二维岩石圈模型。我们的模型表明，如果该地区下方存在推断为元古代的中度亏损岩石圈地幔，那么威尔克斯冰下盆地下方更可能是较浅的莫霍面。然而，如果在上地幔中发生了再富集过程，例如由于罗斯期俯冲作用，那么更倾向于较深的莫霍面情景。我们得出结论，需要进行三维岩石圈建模，并结合横贯南极山脉内陆地区新的地震信息，以帮助解决这一争议，从而减少东南极冰盖这一关键区域下方地热热流估算的不确定性。
The lithospheric structure of Antarctica is still underexplored. Moho depth estimate studies are in disagreement by more than 10 km in several regions, including, for example, the hinterland of the Transantarctic Mountains. Taking account the sparseness of seismological stations and the nonuniqueness of potential field methods, inversions of Moho depth are performed here based on satellite gravity data in combination with currently available seismically constrained Moho depth estimates. Our results confirm that a lower density contrast at the Moho is present under East Antarctica than beneath West Antarctica. A comparison between the Moho depth derived from our inversion and an Airy‐isostatic Moho model also reveals a spatially variable buoyancy contribution from the lithospheric mantle beneath contrasting sectors of East Antarctica. Finally, to test the plausibility of different Moho depths scenarios for the Transantarctic Mountains‐Wilkes Subglacial Basin system, we present 2‐D lithospheric models along the Trans‐Antarctic Mountain Seismic Experiment/Gamburtsev Mountain Seismic experiment seismic profile. Our models show that if a moderately depleted lithospheric mantle of inferred Proterozoic age underlies the region, then a shallower Moho is more likely beneath the Wilkes Subglacial Basin. If however, refertilization processes occurred in the upper mantle, for example, in response to Ross‐age subduction, then a deeper Moho scenario is preferred. We conclude that 3‐D lithospheric modeling, coupled with the availability of new seismic information in the hinterland of the Transantarctic Mountains, is required to help resolve this controversy, thereby also reducing the ambiguities in geothermal heat flux estimation beneath this key part of the East Antarctic Ice Sheet.
基岩侵蚀表面创下前南极东部冰盖范围
影响因子：
5.2
作者：
Paxman, Guy J.;Jamieson, Stewart S.;Ferraccioli, Fausto;Bentley, Michael J.;Ross, Neil;Armadillo, Egidio;Gasson, Edward G.;Leitchenkov, German;DeConto, Robert M.
通讯作者：
DeConto, Robert M.
DOI：
10.1029/2017jb015346
发表时间：
2018-09
期刊：
Journal of Geophysical Research: Solid Earth
影响因子：
--
作者：
W. Shen;D. Wiens;S. Anandakrishnan;R. Aster;P. Gerstoft;P. Bromirski;S. Hansen;I. Dalziel;D. Heeszel;A. Huerta;A. Nyblade;R. Stephen;Terry J. Wilson;J. P. Winberry
通讯作者：
W. Shen;D. Wiens;S. Anandakrishnan;R. Aster;P. Gerstoft;P. Bromirski;S. Hansen;I. Dalziel;D. Heeszel;A. Huerta;A. Nyblade;R. Stephen;Terry J. Wilson;J. P. Winberry
影响因子：
5.2
作者：
Aitken, A. R. A.;Young, D. A.;Siegert, M. J.
通讯作者：
Siegert, M. J.