Abstract
Abstract A detailed analysis of field exposures and grain‐size distribution data for the Pilliga Sandstone within the southern Coonamble Embayment and Oxley Basin indicates a braided stream depositional environment for this unit. From the palaeocurrent data, it is concluded that deposition was dominated by two fluvial systems, one draining Lower Palaeozoic basement rocks to the SW, and the other originating from the SE and possibly fed from uplifted Triassic quartz‐rich sediments of the Sydney Basin. A matrix‐cement of coarse‐grained, well‐ordered kaolinite is typical of this porous sandstone unit, and available evidence points to much of this material being authigenic. The author considers this to have developed during diagenesis of the sandstone through the alteration of unstable detrital minerals by reaction with mobile groundwater.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
