δ2H (Delta Deuterium)
Definition
The ratio of deuterium to hydrogen in a sample expressed in per-mil deviation from VSMOW. Covaries with δ18O along the global meteoric water line because both respond to the same atmospheric fractionation.
- Measures
- 2H/1H (deuterium/hydrogen) ratio
- Reference standard
- VSMOW
- Relationship
- Covaries with δ18O along the meteoric water line
Common questions
Why do δ2H and δ18O tend to move together in a sample?+
Both isotope ratios respond to the same evaporation and condensation fractionation processes in the atmospheric water cycle, so their values trend together and together define the global meteoric water line.
What forensic use does δ2H share with δ18O?+
Both are used in isotope geolocation, where a sample's isotope signature from hair, water, or food is compared against regional reference isoscapes to help narrow down a likely geographic origin.
Related terms
- δ18O (Delta-18-O)
- The ratio of oxygen-18 to oxygen-16 in a sample expressed in per-mil deviation from the Vienna Standard Mean Ocean Water (VSMOW) standard....
- Global Meteoric Water Line (GMWL)
- The linear relationship δ2H = 8 × δ18O + 10 that describes the global co-variation of O and H isotopes in precipitation....
- Isoscape
- A map of isotope ratio variation across a geographic area, derived from systematic sampling of soil, water, plant, or mineral material; used...
- OIPC (Online Isotopes in Precipitation Calculator)
- A web-based tool and database compiling the IAEA GNIP station network data and providing interpolated δ18O and δ2H predictions for any geographic...
- Tissue-Specific Incorporation
- The principle that different tissues record isotope signals over different time windows: enamel permanently records childhood; hair records month-by-month recent history; bone...