"Deep Tine" is the term we use to explain aerification that goes deeper than a typical core aerification on greens, tees and fairways. A routine aerification might go to a depth of 2-3". When we use a larger machine with a longer tine the depth can reach as far down as 10 - 12" or more.
On fairways, we perform a deep tine aerification two to three times per year. Solid, 3/4" tines will penetrate below any hardpan layers (created by years of aerifying to the same depth) and shatter the soil. Fissures are created by vibration movement of the machine thus improving water and air movement.
Disturbance is minimal and the improvement in playing surfaces is enhanced.