Spreading rate dependence of the axial topography and gravity of the Mid‐Atlantic ridge between 22°N and 38°N

A method is developed to quantify the relationship between the ridge axial topography and gravity and the spreading rate along the Mid‐Atlantic Ridge between 22 and 38°N. This relationship reflects the variations of slope of the best‐fit line of topography and gravity spectra with the spreading rate of the ridge segments. The slope of the best‐fit line of topography spectrum becomes smaller as the spreading rate increases, indicating that with increasing spreading rate more energy of the ridge axial topography shifts into high‐frequency bands. The spreading rate dependence of the ridge axial topography may be explained by an anomalous thermal structure beneath the ridge. No significant correlation was found between the slope of the best‐fit line of gravity spectrum and the spreading rate in this region. The lack of spreading rate dependence of the ridge axial gravity may be attributable to the isostatic compensation of the spreading center.

Keywords:

• bathymetry
• gravity
• mid‐ocean ridge
• seafloor spreading