Zircon and apatite fission track (AFT) thermochronology was applied to the James Ross Basin sedimentary rocks from James Ross and Seymour islands. The probable sources of these sediments were generated in Carboniferous to Early Paleogene times (∼315 to 60 Ma). The total depths of individual James Ross Basin formations are discussed. The AFT data were modelled, and the thermal history model was reconstructed for samples from Seymour Island. The first stage after a period of total thermal annealing (when the samples were above 120°C) involved Late Triassic cooling (∼230 to 200 Ma) and is followed by a period of steady cooling through the whole apatite partial annealing zone (PAZ, 60–120°C) to minimum temperature in Paleocene/Early Eocene. The next stage was the maximum burial of sedimentary rocks in the Eocene (∼35 Ma, 1.1–1.8 km) and the final cooling and uplift of Seymour Island sedimentary rocks at ∼35 to 20 Ma.
