Laura Basin hydrogeological inventory

This Laura Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Laura Basin contains sedimentary rocks deposited between 168 and 102 million years ago during the Middle Jurassic to Early Cretaceous. The basin extends offshore beneath the Great Barrier Reef, and forms a bowl-shaped geologic feature. The strata have a maximum thickness of about 1,000 m in the north-central part of the onshore basin. Three main stratigraphic units comprise the stratigraphic succession of the Laura Basin, these being the Rolling Downs Group (Late Aptian to Albian, Cretaceous), the Gilbert River Formation (Lower Cretaceous to Jurassic) and the Dalrymple Sandstone (Upper to Middle Jurassic). The Rolling Downs Group was deposited in a shallow marine environment and has a basal shale unit (the Wallumbilla Formation) with minor siltstone and conglomerate bands overlain by marine silty and sandy claystone. The Gilbert River Formation was deposited in lagoonal to marginal marine environments and is dominated by clay-rich sandstone that is locally glauconitic and interbedded with minor calcareous siltstone, claystone and conglomerate. The Dalrymple Sandstone was deposited in lagoonal and fluvial environments and is dominated by sandstone with lesser claystone, siltstone, conglomerate, tuff and coal. The Laura Basin overlies older rocks of the Permian to Triassic Lakefield Basin, which extends northwards into surrounding marine waters, the Paleozoic metasedimentary rocks of the Hodgkinson region, associated with the Mossman Orogen, and Proterozoic basement rocks.