北京大学学报（自然科学版）2025，Vol.61Issue(5)：891-901,11.DOI:10.13209/j.0479-8023.2025.025
大西洋中脊30.00°—31.55°N区域断层构造与岩浆供给的关系
Magmatic and Tectonic Crustal Accretion at the Mid-Atlantic Ridge between 30.00°N and 31.55°N
摘要
Abstract
Utilizing high-precision shipborne multibeam bathymetry and gravity anomaly data,we analyzed the fault structures and magmatic characteristics of the Mid-Atlantic Ridge(MAR)segment between 30.00°N and 31.55°N.Firstly,based on the multibeam bathymetry data,slope,roughness,and curvature information in the study area,we identified two main geomorphological patterns:faults and volcanic features.The fault geomorphology was further divided into three typical fault styles:detachment faults,E-type faults,and C-type faults.In the entire region,E-type faults are mainly distributed within the area 20-50 km away from the ridge axis on both flanks,while C-type faults are more densely distributed in the near-axis region and the rift valley of the MAR,within 0-20 km from the axis.Subsequently,the horizontal fault heaves and tectonic strain rate(T)values were calculated based on 13 cross-axis profiles.The results indicate a significant asymmetric spreading phenomenon in the region.In areas with sufficient magma supply,or near the ridge axis and the rift valley,the T values are relatively small,typically forming a thicker oceanic crust and C-type faults with smaller horizontal fault offsets.In areas with depleted magma supply or farther away from the mid-ocean ridge,a thinner oceanic crust is often formed,with larger T values and more prevalent E-type faults and detachment faults with larger horizontal fault offsets.关键词
大西洋中脊(MAR)/多波束地形/构造作用/岩浆活动Key words
Mid-Atlantic Ridge(MAR)/multibeam bathymetry/tectonism/magmatism引用本文复制引用
冯博,李江海..大西洋中脊30.00°—31.55°N区域断层构造与岩浆供给的关系[J].北京大学学报（自然科学版）,2025,61(5):891-901,11.基金项目
中国大洋"十三五"课题(DY135-S2-1-01,DY135-S1-1-03)资助 （DY135-S2-1-01,DY135-S1-1-03）
