Welcome to the 3-dimensional Reference Earth Model Webpage!

REM-3D was a project funded by the National Science Foundation designed and led by co-PI's Ved Lekic, Barbara Romanowicz, and Adam Dziewonski. Raj Moulik worked on the project while a postdoctoral researcher at the University of Maryland, College Park. You can read more about the goals of the project here.

Thus far, the REM-3D project has compiled, reconciled and distributed a massive dataset of long period (25-250s) surface wave dispersion measurements.  This work has, for the first time, rigorously quantified the uncertainty of phase dispersion measurements across groups and methods. The methods and outcomes of this work are described in Moulik, Lekic, Romanowicz_et_al. (2022).

The reference data set summarizes measurements of dispersion of fundamental-mode surface waves and up to six overtone branches from 44,871 earthquakes recorded on 12,222 globally distributed seismographic stations. Dispersion curves are specified at a set of reference periods between 25 and 250 s to determine propagation-phase anomalies with respect to a reference Earth model. The reference dataset is created from contributions by Ekstrom (2011), Ritsema et al. (2011), Ma et al. (2014), Schaeffer and Lebedev (2018), Trampert (2015), Ho and Priestley (2019), Beucler et al. (2003), Debayle (2018), and Priestley et al. (2019), as detailed in Table 1 of the paper. Empirically determined observational uncertainties (1 sigma) for each wave type, branch number and period can be found in Table 3 of the paper.

The summary datasets in ASCII table form can be found and downloaded from here. Their format is described in Table A1 of Moulik, Lekic, Romanowicz_et_al. (2022).