Use LOG to insert the logarithm of the value for a base. This enables you to represent very high values using a smaller frame of reference. For example, LOG is used to assess seismic activity such as earthquakes.
LOG uses this syntax: LOG(value, base)). For exampl, LOG(4, 100,000))= 0.12
Use LOG10 to insert the base-10 logarithm of a number that you specify. This function uses this syntax: