Comment on “Uranium series dating of Great Artesian Basin travertine deposits: Implications for palaeohydrogeology and palaeoclimate” by Priestley et al. (2018)

Widespread travertine deposits occur in the southwestern Great Artesian Basin (GAB) in central Australia. Priestley et al. (2018) reported uranium-series ages of travertine deposits and concluded that elevated travertine deposition rates are synchronous with wet periods and that times of travertine deposition represent times of high regional rainfall. We propose an alternative explanation that CO2 degassing from the mantle associated with active faulting played a major role in travertine precipitation in the southwestern GAB. •We challenge the notion that travertine deposition is climatically controlled in the southwestern Great Artesian Basin.•Travertine deposition also occurred during dry climate periods.•We argue that a connection between travertine deposition and tectonically-controlled CO2 degassing is more likely.