Magma-induced axial subsidence during final-stage rifting: Implications for the development of seaward-dipping reflectors
Magma-induced axial subsidence during final-stage rifting: Implications for the development of seaward-dipping reflectors
复制标题
裂谷作用末期岩浆诱发的轴向沉降：对向海倾斜反射体发育的启示
DOI：
10.1130/ges01076.1
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发表时间：
2015-06
期刊：
影响因子：
2.5
通讯作者：
G. Corti;A. Agostini;D. Keir;J. Wijk;I. Bastow;G. Ranalli
中科院分区：
文献类型：
--
作者：
G. Corti;A. Agostini;D. Keir;J. Wijk;I. Bastow;G. Ranalli
A consensus is emerging from studies of continental rifts and rifted margins worldwide that significant extension can be accommodated by magma intrusion prior to the development of a new ocean basin. However, the influence of loading from magma intrusion, lava extrusion, and sedimentation on plate flexure and resultant subsidence of the basin is not well understood. We address this issue by using three-dimensional flexural models constrained by geological and geophysical data from the Main Ethiopian Rift and the Afar Depression in East Africa. Model results show that axial mafic intrusions in the crust are able to cause significant downward flexure of the opening rift and that the amount of subsidence increases with decreasing plate strength accompanying progressive plate thinning and heating during continental breakup. This process contributes to the tilting of basaltic flows toward the magma injection axis, forming the typical wedge-shaped seaward-dipping reflector sequences on either side of the eventual rupture site as the new ocean basin forms.
