Earth Crustal Model 1 (ECM1): A 1° x 1° Global Seismic and Density Model

Earth Crustal Model 1 (ECM1) is a 1° x 1° global crustal model that describes the thickness of the crust, including the overlying sediments, and the corresponding seismic velocities of P-waves, S-waves, and density. Seismic velocities and density of the uppermost mantle are also specified. ECM1 uses the model parameterization adopted by CRUST5.1 and CRUST1.0 whereby the crust is described by tiles with eight layers of variable thickness for ice, water, sediments, and the crystalline crust. ECM1 differs from previous crustal models in several aspects: (1) the sediment model incorporates newly published oceanic and continental compilations of sediment thickness; (2) the application of a vastly expanded database of 19,200 seismic measurements which sample seismic velocities within the sedimentary cover, crystalline crust and uppermost mantle; (3) the continental S-wave velocity is based on field measurements, unlike other models which estimate the S-wave velocity using the measured P-wave velocity and an assumed Vp/Vs ratio; (4) a new digital map of crustal types is used to interpolate seismic velocities for unmeasured areas. We use field measurements of crustal structure to calculate the Vp, Vs, Vp/Vs and density at 5 km intervals for continents and 2 km intervals for oceans down to Moho depth for each crustal type. We calculate the surface area, volume, and mass of Earth's entire crust, as well as for each crustal type within oceans, continents, and their margins.