Topographic evolution of the western United States since the early Miocene
Topographic evolution of the western United States since the early Miocene
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中新世早期以来美国西部的地形演化
DOI：
10.1016/j.epsl.2019.02.029
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发表时间：
2019
影响因子：
5.3
通讯作者：
Liu, Lijun
中科院分区：
文献类型：
--
作者：
Zhou, Quan;Liu, Lijun
美国西部高地貌的起源被归因于地壳/岩石圈均衡或动态地形，但它们的相对贡献仍然不受限制。在这里，我们使用重力、残余地形和地球动力学模型来研究这个问题。我们首先评估了均衡平衡的两种端元情景：地壳均衡和岩石圈均衡。这两种情况都导致了美国西部构造活动中突出的负地幔残余重力和不切实际的地壳/岩石圈密度结构，需要在下面存在低密度地幔。负地幔残余重力与估计的正残余地形和计算的由于下方存在热的软流圈地幔而引起的动态抬升是一致的。地球动力学模拟进一步揭示，这种向陆地迁移的动力隆升起源于中中新世以来热的太平洋地幔通过胡安德·富卡板块的裂隙和边缘向东侵入。结合动态地形和岩石圈均衡得到的美国西部古地形图符合几个观测约束条件，包括内华达山脉的幕式隆起、爱达荷州基岩的中中新世后隆起、B&R大部分地区的持续下沉以及科罗拉多高原中部自20 Ma以来的基本稳定的地形。
The origin of the high topography within the western United States has been attributed to either crustal/lithospheric isostasy or dynamic topography, but their relative contributions remain unconstrained. Here we investigate this problem using gravity, residual topography and geodynamic modeling. We first evaluate two end-member scenarios of isostatic balance: crustal isostasy and lithospheric isostasy. Both cases lead to prominent negative mantle residual gravity within the tectonically active western U.S. and unrealistic crustal/lithospheric density structures, requiring the presence of low-density mantle underneath. The negative mantle residual gravity is consistent with both the estimated positive residual topography and calculated dynamic uplift due to the presence of hot asthenospheric mantle underneath. Geodynamic modeling further reveals that this landward migrating dynamic uplift originates from the eastward intrusion of the hot Pacific mantle through tears and edges of the Juan de Fuca slab since middle Miocene. The estimated paleotopography maps by combining dynamic topography and lithosphere isostasy over the western U.S. are consistent with several observational constraints, including episodic uplifts of the Sierra Nevada, post-mid-Miocene uplift of the Idaho batholith, the sustaining subsidence within most of the B&R, and the largely stable topography of central Colorado Plateau since 20 Ma.
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影响因子：
56.9
作者：
Lijun Liu;D. Hasterok
通讯作者：
Lijun Liu;D. Hasterok
根据重力和热流数据建立黄石-斯内克河平原火山系统的密度和岩石圈强度模型
影响因子：
2.9
作者：
Katrina R. DeNosaquo;Robert B. Smith;A. Lowry
通讯作者：
A. Lowry
影响因子：
5.3
作者：
Quan Zhou;Jiashun Hu;Lijun Liu;T. Chaparro;D. Stegman;M. Faccenda
通讯作者：
Quan Zhou;Jiashun Hu;Lijun Liu;T. Chaparro;D. Stegman;M. Faccenda
沿黄石热点轨迹 II 的质量传递：对地幔岩浆体积的运动学约束
影响因子：
2.9
作者：
D. Rodgers;M. McCurry
通讯作者：
M. McCurry
落基山脉和科罗拉多高原地幔驱动的动态隆起及其地表响应：走向统一的假说
DOI：
--
发表时间：
2012
期刊：
影响因子：
--
作者：
K. Karlstrom;D. Coblentz;K. Dueker;W. Ouimet;E. Kirby;J. Wijk;B. Schmandt;S. Kelley;G. Lazear;L. Crossey;R. Crow;A. Aslan;A. Darling;R. Aster;J. MacCarthy;S. Hansen;J. Stachnik;D. Stockli;R. V. Garcia;M. Hoffman;R. McKeon;J. Feldman;M. Heizler;M. Donahue
通讯作者：
M. Donahue