Core–mantle boundary Core–mantle boundary The core–mantle boundary (CMB in the parlance of solid earth geophysicists) of the Earth lies between the planet's silicate mantle and its liquid iron-nickel outer core. This boundary is located at approximately 2891 km (1796 mi) depth beneath the Earth's surface. The boundary is observed via the discontinuity in seismic wave velocities at that depth due to the differences between the acoustic impedances of the solid mantle and the molten outer core. P-wave velocities are much slower in the outer core than in the deep mantle while S-waves do not exist at all in the liquid portion of
What We Do in Secret What We Do in Secret What We Do In Secret is an American Christian hardcore band from Memphis, Tennessee. They have toured with bands such as War of Ages, Phinehas, Silent Planet, Sleepwave, We Came As Romans, '68, For Today and Norma Jean. They have released two EPs. What We Do In Secret was formed in Memphis in March 2012 by Josh Adams, Drew Nance, Devin Harris and Nathan Moody. They recorded their first EP, "New Eyes", and released it on August 31, 2013. Moody left the band after this and was replaced by Clay Crenshaw and Austin Barnes. The