The Significance of Densely Sampled Observations of Mantle Dynamic Topography
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Dynamic topography is generated from mantle convection and can be isolated from isostatic topography using observational constraints. Quantifying observable dynamic topography yields valuable information on mantle convective processes. This study presents a revised and augmented dataset of 10,874 residual depth measurements from oceanic crust, which originate from 7,601 seismic experiments. The isostatic component of topography is identified and removed by correcting for sedimentary loading and crustal thickness variation. Methodological improvements are implemented for both sedimentary and crustal corrections. Residual depth measurements typically deviate by $\pm$1~km from the predicted plate cooling trend. Positive and negative anomalies correlate with independent geological and geophysical observations of uplift and subsidence. This oceanic dataset is combined with a continental dataset to generate globally continuous spherical harmonic representations out to degree 40. The resultant power spectrum demonstrates that most power occurs at degree 2 (i.e., wavelengths of $\sim