Continental Shelf Sediments: Southern Queensland and Northern New South Wales

摘要

Sands are predominant over the entire continental shelf, and mud is absent or only a minor component of the sediments. The amount of gravel, largely biogenic, is high in some places, but it has a scattered distribution. The amount of carbonate on the outer shelf is relatively low as a result of the formation of authigenic minerals. The terrigenous component of the sediments is dominated by quartz. Four types of quartz grains were identified on the basis of roundness, sorting, and grainsize. Skeletal carbonate components include manly foraminifera, molluscs, bryozoa, echinoderms, and calcareous red algae. Intraclasts with either micrite or sparite cement are common and various types of carbonate cements have developed. Authigenic components of the shelf sediments consist of glauconite, goethite, and apatite. Sediments were analysed for iron, arsenic, phosphorus, and titanium.