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Sonic logging is a well logging tool that provides a formation’s interval transit time, designated as Δ t {\displaystyle {\Delta }t} , which is a measure of a how fast elastic seismic compressional and shear waves travel through the formations. Geologically, this capacity varies with many things including lithology and rock textures, most notably decreasing with an increasing effective porosity and increasing with an increasing effective confining stress. This means that a sonic log can be used to calculate the porosity, confining stress, or pore pressure of a formation if the seismic velocity of the rock matrix, V m a t {\displaystyle V_{mat}} , and pore fluid, V l {\displaystyle V_{l}} , are known, which is very useful for hydrocarbon exploration.