Age of Minerals and Rocks containing Pure Uranium and Pb-206 Calculator

Age Calculation Formula:

\[ t_{U/Pb} = 15.15 \times 10^9 \times \log_{10}\left(1 + \frac{1.158 \times Pb_{206}}{U_{238}}\right) \]

Age of Sample (years):

Definition: This calculator estimates the age of minerals and rocks based on the ratio of uranium-238 to lead-206 isotopes.

Purpose: It helps geologists and researchers determine the age of geological samples using radiometric dating techniques.

The calculator uses the formula:

\[ t_{U/Pb} = 15.15 \times 10^9 \times \log_{10}\left(1 + \frac{1.158 \times Pb_{206}}{U_{238}}\right) \]

Where:

Explanation: The formula calculates the time elapsed since the mineral/rock formed based on radioactive decay of U-238 to Pb-206.

Details: This method provides accurate age determinations for geological samples, helping understand Earth's history and geological processes.

Tips: Enter the measured amounts of Pb-206 and U-238 in milligrams. Both values must be > 0 for calculation.

Q1: What is the half-life of U-238?
A: Uranium-238 has a half-life of approximately 4.468 billion years.

Q2: Why is the 1.158 factor used?
A: This accounts for the difference in atomic weights between U-238 and Pb-206.

Q3: How accurate is this dating method?
A: When properly applied, U/Pb dating can be accurate to within 1% of the true age.

Q4: What types of samples can be dated?
A: Zircon crystals are most commonly used, but other uranium-bearing minerals can also be dated.

Q5: What's the oldest dateable age?
A: In theory, this method can date samples as old as the Earth itself (~4.5 billion years).