Research applications of logarithmic functions as mathematical models. Some idea

Research applications of logarithmic functions as mathematical models. Some ideas include but are not limited to: pH (acidity of solutions), intensity of sound (decibels), brightness of stars, human memory, progress over time in a sport, and profit over time.
Choose an area of interest from above or provide one of your own, and explain how logarithmic functions are used.
Provide at least one example.