Uplift at lithospheric swells—I: seismic and gravity constraints on the crust and uppermost mantle structure of the Cape Verde mid‐plate swell
Uplift at lithospheric swells—I: seismic and gravity constraints on the crust and uppermost mantle structure of the Cape Verde mid‐plate swell
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岩石圈隆起处的隆升：地震和重力对佛得角板中隆起的地壳和上地幔结构的约束
DOI：
10.1111/j.1365-246x.2010.04641.x
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发表时间：
2010
影响因子：
2.8
通讯作者：
A. Krabbenhoeft
中科院分区：
文献类型：
--
作者：
Wilson;C. Peirce;A.B. Watts;I. Grevemeyer;A. Krabbenhoeft
广角地震数据已被用来确定佛得角中部板块隆起之下地壳和上地幔的速度和密度结构。地震模型显示，这是一个“标准”的海洋地壳，厚度为1.88公里，没有直接证据表明地壳底部存在低密度天体。然而，在地震模型提供的限制和分辨率范围内的重力异常建模并不排除在隆起顶部之下厚达3公里的地壳底板层。模拟表明，虽然地震约束的地壳结构解释了短波长的自由空气重力异常，但它未能完全解释长波长的异常。主要的差异是在隆起的顶部，重力异常，校正地壳结构后，比它的侧翼高约30 mGal。如果隆起顶部100 km的地幔密度比周围低30 kg m−3，则可以解释更高的重力。缺乏证据的低密度和速度在最上层的地幔，高密度和速度在下地壳，表明既不是一个耗尽隆起根或地壳底板的起源所观察到的比预测的水深浅，相反，膨胀是最有可能的支持动态隆起与一个令人不安的低密度软流圈地幔。
Wide-angle seismic data have been used to determine the velocity and density structure of the crust and uppermost mantle beneath the Cape Verdes mid-plate swell. Seismic modelling reveals a ‘standard’ oceanic crust, ∼8 km in thickness, with no direct evidence for low-density bodies at the base of the crust. Gravity anomaly modelling within the constraints and resolution provided by the seismic model, does not preclude, however, a layer of crustal underplate up to 3 km thick beneath the swell crest. The modelling shows that while the seismically constrained crustal structure accounts for the short-wavelength free-air gravity anomaly, it fails to fully explain the long-wavelength anomaly. The main discrepancy is over the swell crest where the gravity anomaly, after correcting for crustal structure, is higher by about 30 mGal than it is over its flanks. The higher gravity can be explained if the top 100 km of the mantle beneath the swell crest is less dense than its surroundings by 30 kg m−3. The lack of evidence for low densities and velocities in the uppermost mantle, and high densities and velocities in the lower crust, suggests that neither a depleted swell root or crustal underplate are the origin of the observed shallower-than-predicted bathymetry and that, instead, the swell is most likely supported by dynamic uplift associated with an anomalously low density asthenospheric mantle.
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影响因子：
2.8
作者：
R. White;R. Detrick;M. Sinha;M. Cormier
通讯作者：
R. White;R. Detrick;M. Sinha;M. Cormier
佛得角地幔柱采样：佛得角群岛圣安涛熔体成分的演化
影响因子：
3.9
作者：
P. Holm;J. Wilson;B. Christensen;L. Hansen;S. L. Hansen;K. M. Hein;A. Mortensen;R. Pedersen;S. Plesner;M. Runge
通讯作者：
M. Runge
影响因子：
5.3
作者：
DAVIS, EE;LISTER, CRB
通讯作者：
LISTER, CRB
DOI：
--
发表时间：
1976
期刊：
影响因子：
--
作者：
B. Dash;M. Ball;G. King;L. W. Butler;P. Rona
通讯作者：
P. Rona
西非佛得角群岛侧翼塌陷和大规模山体滑坡
影响因子：
3.7
作者：
Masson;T.P LeBas;I. Grevemeyer;W. Weinrebe
通讯作者：
W. Weinrebe