OCEANIC TRANSPORT OF FOSSIL DAMMAR RESIN - THE CHEMISTRY OF COASTAL RESINITES FROM SOUTH-AUSTRALIA

Fragments of resin and fossilised resin (resinites) occasionally wash ashore along the southern Australian coast. Chemical and isotopic anal yses were carried out on a suite of coastal and reference resinites to determine the likelihood of a local, as opposed to a distant, origin. All of the coastal resinites were found to contain a polymer based on the sesquiterpenoid cadinene skeleton and were markedly different to the diterpenoid resinites found in local Victorian coals. The coastal resinites closely resemble both fossil and recent dammar resin-a mater ial associated primarily with the tropical angiosperm hardwoods of Sou theast Asia, and one which has no known Australian source. Minor varia tions in the composition of our resinite samples are attributed to dif ferences in their thermal history. These findings confirm the viabilit y of long-distance oceanic transport, not only for the resinites but a lso for the waxy bitumens that strand along the same coastline. Analyt ical data on the coastal resinites also help to clarify the role of da mmar resin in generating bicadinanes-a class of source and age-specifi c triterpanes found commonly in the Cainozoic oils and sediments of So utheast Asia.