Description
Summary:Maintenance and Update Frequency: unknown Statement: Sediment samples were exported from Geoscience Australia's Marine Sediments database (MARS), an Oracle database developed by Geoscience Australia in line with ANZLIC data standards. A subset of this data was selected for use in predicting spatial distribution of mud content based on a set of criteria (see Li et al. 2010). Predicting the spatial distribution of mud content at a 0.01 decimal degree resolution was undertaken using a combined method of random forest and ordinary kriging (see Li et al. 2010 and 2011). The spatial interpolation method used was experimentally selected from over 40 methods/sub-methods based on assessment of predictive errors (Li et al. 2010 and 2011). The predictions were then imported to ArcGIS, and ArcGRID and ascii raster files were generated. Final raster files are in Geographic WGS 84 coordinate system with a 0.01 dd spatial resolution. File sizes are approximately is 79 MB (ArcGRID) and 135 MB (ascii) with dimension of 5396 x 3831 cells. This dataset provides the spatially continuous data of seabed mud content (sediment fraction < 63 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.01 decimal degree resolution raster format. The dataset covers the Australian continental EEZ, including seabed surrounding Tasmania. It does not include areas surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands or Australia's marine jurisdiction off of the Territory of Heard and McDonald Islands and the Australian Antarctic Territory. This dataset supersedes previous predictions of sediment mud content for the Australian Margin with demonstrated improvements in accuracy. Accuracy of predictions varies based on density of underlying data and level of seabed complexity. Artefacts occur in this dataset as a result of insufficient samples in relevant regions. This dataset is intended for use at national and regional scales. The dataset may not be ...