Abstract:
This paper analyzed C, H and O isotopes of amber from Baltic, Dominica, Mexico, Burma, and copals with Stable Isotope Ratio Mass Spectrography (CRMS).Firstly, δ
13C of ambers ranges between -19.38‰ and -25.76‰.δ
13C of Burman ambers ranges between -19.38‰ and -22.90‰ with an average of -21.15‰.δ
13C of Baltic ambers ranges between -22.76‰and -25.76‰ with an average of -24.35‰, and δ
13C of Dominican ambers ranges between -23.57‰and -26.63‰ with an average of -24.99‰.Average C isotopes of ambers from those areas are different.Secondly, there is a good linear relation between δ
13C of ambers and their formation ages.With the increase in geological ages of natural ambers,
13C of ambers increases regularly.It is thus suggested that maturity degree of ambers (from high to low) is the Burman amber, Baltic amber, Dominican and Maxican amber.Thirdly, δ
13C of copals ranges between -26.82‰ and -29.94‰ with an average of -28.55‰.Based on data of experimental analyses, it is suggested that boundary value between amber and copal is -27.00‰ (+0.18, -3.00), which may provide an isotopic evidence to distinguish between amber and copal.Fourthly, δD of Burman ambers ranges between -195.90‰ and -244.40‰ with an average of -222.59‰.δD of Baltic ambers ranges between -235.90‰and -268.60‰ with an average of -253.46‰.δD of Dominican ambers ranges between -203.30‰ and -228.50‰ with an average of -219.05‰, and that of Mexican ambers is -218.90‰.Change inδD of ambers is closely related with latitude of amber formation.That is, with the increase of latitude, δD gradually decreases.Fifthly, two-dimensional space of
13C-
18Oisotopes and D-
18Oisotopes, and three-dimensional space
13C, D,
18Oisotopes of ambers vary from different producing areas.It is thus suggested that combinations of C, H and O isotopes of ambers can trace producing areas.