Oxygen isotope ratio cycle

Oxygen (chemical symbol O) has three naturally occurring isotopes: 16O, 17O, and 18O, where the 16, 17 and 18 refer to the atomic mass.

Additional factors can affect the efficiency of the distillation, such as the direct precipitation of ice crystals, rather than liquid water, at low temperatures.

[1] In laboratories, the temperature, humidity, ventilation and so on affect the accuracy of oxygen isotope measurements.

Researchers need to avoid improper or prolonged storage of the samples for accurate measurements.

As colder temperatures spread toward the equator, water vapor rich in 18O preferentially rains out at lower latitudes.

The remaining water vapor that condenses over higher latitudes is subsequently rich in 16O.

A higher abundance of 18O in calcite is indicative of colder water temperatures, since the lighter isotopes are all stored in the glacial ice.

[4] Earth's dynamic oxygenation evolution is recorded in ancient sediments from the Republic of Gabon from between about 2,150 and 2,080 million years ago.