The rocks are mostly rich in quartz and metasedimentary, overlain by younger Mesozoic rocks and the Devonian backarc basin sediments of the Adavale Basin.
Detrital zircon dating of Thomson Orogen rocks indicates ages between 510 and 495 million years ago, spanning the Cambrian to the Devonian.
[citation needed] In the northern part of the Thomson Orogen, rifting in the late Neoproterozoic is recorded in the lower metamorphic rocks of the Anakie Province.
[1] In the south, the Thomson Orogen borders the Lachlan Orogen, separated by the Olepoloko Fault in the west and the Louth-Eumarra Shear Zone in the east.
The Thomson Orogen extends east under the Bowen Basin and based on seismic reflection data, seems to the underlie the western edge of the New England Orogen.