The dispersed organic matter content of drill cuttings samples from the subject wells was examined microscopically to assess its hydrocarbon potential. In general it appears that the Cretaceous and Permian sediments are unlikely to be good source rocks, while on both geological and geochemical evidence the Jurassic and Triassic sediments have more promising source character, and so if mature could be possible source rocks. The most likely source rocks for the oil found in Poolowanna 1 are the Lower Jurassic or Triassic sediments, and these would be better targets than the Permian sequence for future drilling, especially where they are more deeply buried and of higher rank than in Macumba 1. The Poolowanna 1 vitrinite reflectances are higher than those from Macumba 1 and they may be even higher further to the east.