Abstract: A new method is proposed here to identify the volcanic subfacies/facies with the cuttings. The general flowchart is true cuttings selection→cutting thin section preparation→thin section observation with microscope→subfacies/facies identification. The volcanic subfacies/facies finally is identified according to the typical characteristics of lithology, structure and texture observed under the microscope. The resolution equals to the cutting sampling interval (1 m, in general). The accuracy is more than 90% compared to the core observation. This method was effective to verify the lithology as well as the volcanic facies. It has been proved as an effective way to promote the resolution of inter-well lithology and facies correlation based on the applications in 15 wells in Dongling, Southern Songliao Basin.

Key words: true volcanic cuttings, cutting sampling, volcanic subfacies identification, Dongling area