DOI: 10.1016/j.tecto.2019.228307
论文题名: Evidence of ridge propagation in the eastern Gulf of Mexico from integrated analysis of potential fields and seismic data
作者: Filina I. ; Liu M. ; Beutel E.
刊名: Tectonophysics
ISSN: 00401951
出版年: 2020
卷: 775 语种: 英语
英文关键词: Geophysical prospecting
; Seismic response
; Seismic waves
; Compressional velocities
; Crustal earthquakes
; Different thickness
; Integrated analysis
; Magmatic materials
; Ridge propagation
; Tectonic structure
; Two-layered structures
; Data flow analysis
; asymmetry
; crustal structure
; potential field
; seismic data
; seismic velocity
; seismicity
; spreading center
; wave propagation
; Atlantic Ocean
; Gulf of Mexico
英文摘要: Integrated analysis of gravity, magnetic, and seismic data reveals two phases of spreading in the eastern Gulf of Mexico (GOM) including two distinct spreading centers, suggesting a major ridge reorganization during the opening of the eastern part of the GOM. Ridge propagation between the two spreading episodes explains the following observations: 1) the drastic asymmetry in the oceanic domain of northeastern GOM, 2) the presence of two distinct crustal zones with dramatically different thickness and physical properties, and 3) the observed seismicity within the oceanic domain that is not aligned with any known tectonic structure. The initial Late Jurassic spreading center (~160 Ma) resulted in thin (~5 km) and uniform oceanic crust with a fast compressional velocity (7 km/s). Based on our analysis, the estimated full spreading rate of this older spreading event is less than 1 cm/yr. The spreading regime changed in Early Cretaceous around 150 Ma, resulting in a propagation (i.e., jump) of the spreading center. The new spreading episode was characterized by a change in spreading direction and increased magma supply as it produced thicker (up to 9 km) oceanic crust with a typical two-layered structure. Despite the increase in magmatic material, the full rate of this younger spreading event estimated from our analysis is only slightly faster (1.1 cm/yr assuming that spreading ceased at 137 Ma). The later conclusion is consistent with the morphology of the spreading centers mapped by seismic data. Our analysis shows that recent deep crustal earthquakes in the middle of the Gulf of Mexico are aligned with the boundary between the two identified distinct oceanic zones, referred here as a pseudofault. © 2019 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/170585
Appears in Collections: 气候变化与战略
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作者单位: Department of Earth and Atmospheric Sciences, the University of Nebraska, Lincoln, United States; Department of Earth and Atmospheric Sciences, the University of Houston, United States; Department of Geology and Environmental Geoscience, the College of Charleston, United States
Recommended Citation:
Filina I.,Liu M.,Beutel E.. Evidence of ridge propagation in the eastern Gulf of Mexico from integrated analysis of potential fields and seismic data[J]. Tectonophysics,2020-01-01,775