4.5 Article

Bathymetry of Valdivia Bank, Walvis Ridge, South Atlantic Ocean: Implications for Structure and Geologic History of a Hot Spot Plateau

期刊

GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
卷 23, 期 11, 页码 -

出版社

AMER GEOPHYSICAL UNION
DOI: 10.1029/2022GC010624

关键词

multibeam bathymetry; Walvis Ridge; oceanic plateau; hot spot volcanism; seamount; Valdivia Bank

资金

  1. National Science Foundation
  2. NSF [OCE-1832197]
  3. German Federal Ministry for Education and Research (BMBF) [03G0233A]

向作者/读者索取更多资源

This study developed a bathymetric map of Valdivia Bank using various data sets, revealing previously unknown geological features and demonstrating ongoing geological activities in oceanic plateaus.
Valdivia Bank is an oceanic plateau in the South Atlantic formed by hot spot magmatism at the Mid-Atlantic Ridge during the Late Cretaceous. It is part of the Walvis Ridge, an aseismic ridge and seamount chain widely considered to be formed by age-progressive volcanism from the Tristan-Gough plume. To better understand the formation and history of this edifice, we developed a bathymetric map of Valdivia Bank by merging available multibeam echosounder data sets with a bathymetry grid based mainly on satellite altimetry (SRTM15+). The bathymetric map reveals previously unresolved features including extensive rift grabens, volcanic mounds and knolls, and large-scale sediment transport systems. After Valdivia Bank was emplaced and probably eroded at sea level, it underwent a period of rifting, followed by a secondary magmatic pulse that caused regional uplift to sea-level, followed by subsidence to current depths. Shallow banks at depths of similar to 1,000 m are the result of a thick sediment pile atop uplifted volcanic crust. Several shallower mounds (similar to 1,000-520 m) and a guyot (similar to 220 m) likely resulted from coral reef growth atop one or more volcanic pedestals formed during the younger Cenozoic magmatic event. As sediments accumulated on the shallow platforms, sediment transport systems developed as gullies, channels and mass transport deposits carved valleys and troughs, shedding sediment into abyssal fans at the plateau base. The new bathymetric map demonstrates that oceanic plateaus are geologically active long after initial emplacement.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.5
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据