AbstractAmber from the Cretaceous and Tertiary periods in North America is characterized for the first time by nuclear magnetic resonance spectroscopy. Cretaceous samples from Cedar Lake in western Canada have nearly identical spectra to samples from New Jersey. There also are strong similarities between the spectra of these samples and those from Alaska and from the state of Washington. Tertiary samples from Arkansas, on the other hand, have quite distinct spectra. A common or similar paleobotanical origin is suggested for amber from diverse locations in North America, but amber also was produced from other, quite distinct trees as from Arkansas.
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