The Layered Geology of Australia web map service is a seamless national coverage of Australia’s surface and subsurface geology. Geology concealed under younger cover units are mapped by effectively removing the overlying stratigraphy (Liu et al., 2015). This dataset is a layered product and comprises five chronostratigraphic time slices: Cenozoic, Mesozoic, Paleozoic, Neoproterozoic, and Pre-Neoproterozoic. As an example, the Mesozoic time slice (or layer) shows Mesozoic age geology that would be present if all Cenozoic units were removed. The Pre-Neoproterozoic time slice shows what would be visible if all Neoproterozoic, Paleozoic, Mesozoic, and Cenozoic units were removed. The Cenozoic time slice layer for the national dataset was extracted from Raymond et al., 2012. Surface Geology of Australia, 1:1 000 000 scale, 2012 edition. Geoscience Australia, Canberra.

The Realms data set was created as one of three broad-scale data layers to facilitate the definition of Primary and Secondary compartments. The Realms data is provided so that the logic of the compartment creation can be understood. With regards to spatial scale, the Realms data set represents the smallest scale product, as shown in the hierarchical listing for all of the polygon data sets shown below: - Coastal Realms (1:5 000 000) - Coastal Regions (1:1 000 000) - Coastal Divisions (1:250 000) - Primary Compartments (1:250 000 - 1:100 000) - Secondary Compartments (1:100 000 - 1:25 000)

The Exploring for the Future Project Areas web service depicts the spatial extents of project work undertaken as part of Geoscience Australia's $100.5 million initiative dedicated to boosting investment in resource exploration in Australia. Each project area extent has been generated by aggregating all project work sites into an envelope polygon. An indicative spend on each f the projects is also given.

This point data set was created to identify locations on (or near) the Australian coastline which were considered to represent significant changes in key environmental attributes of the coast as they pertain to sediment movement in the coastal zone. This data was created during and subsequent to the technical workshop hosted by Geoscience Australia in Canberra from 16-18 October 2012. This workshop brought together the team of Australian coastal science experts listed below. - Prof. Bruce Thom - University of Sydney and the Wentworth Group - Prof. Andy Short - University of Sydney - Prof. Colin Woodroffe - University of Wollongong - Dr. Ian Eliot - University of Western Australia - Mr. Chris Sharples - University of Tasmania - Dr. Brendan Brooke - Geoscience Australia - Dr. Scott Nichol - Geoscience Australia The technical workshop had the goal of creating regional (primary) and sub-regional (secondary) scale coastal sediment compartments - spatial zones (represented by polygons) within (or between) which sediment movement could be considered on scales and timeframes relevant to coastal management. The first step in this process involved the expert panel identifying and defining boundary points along the Australian coastline, after which the expert panel assigned relevant environmental attributes to each point. Following the development of the boundary points data set, breaklines representing the coast-perpendicular compartment boundaries were generated by extending a line from the defined offshore bathymetric contour to the defined onshore elevation contour. In every case a compartment breakline extends seaward and landward of its boundary point.

The Divisions data set was created as one of three broad-scale data layers to facilitate the definition of Primary and Secondary compartments. The Divisions data is provided so that the logic of the compartment creation can be understood. With regards to spatial scale, the Divisions data set represents one of the mid-scale products, as shown in the hierarchical listing for all of the polygon data sets shown below: - Coastal Realms (1:5 000 000) - Coastal Regions (1:1 000 000) - Coastal Divisions (1:250 000) - Primary Compartments (1:250 000 - 1:100 000) - Secondary Compartments (1:100 000 - 1:25 000)

It is with great interest that we read the paper by Mueller (2015) who proposes that the majority of small pockmarks with diameters less than about 10 m on the northwest shelf of Australia may be of biotic origin, created by the fish Epinephelus, the Grouper. This hypothesis is based on a spatial association between pockmarks and Epinephelus at a number of sites on the northwest shelf and elsewhere around Australia, and on recent work undertaken on the habitats and observed behaviours of grouper fish in the Gulf of Mexico who excavate sediment from pre-existing solution cavities (Coleman et al., 2010; Wall et al., 2011). However, we contend that critical details have not been taken into account as part of Mueller's (2015) hypothesis, and additional consideration of existing geologic, geomorphic, sedimentologic and geochemical information is required. To make the science more robust, here we present a more comprehensive overview of the information available.

The Regions data set was created as one of three broad-scale data layers to facilitate the definition of Primary and Secondary compartments. The Regions data is provided so that the logic of the compartment creation can be understood. With regards to spatial scale, the Regions data set represents one of the mid-scale products, as shown in the hierarchical listing for all of the polygon data sets shown below: - Coastal Realms (1:5 000 000) - Coastal Regions (1:1 000 000) - Coastal Divisions (1:250 000) - Primary Compartments (1:250 000 - 1:100 000) - Secondary Compartments (1:100 000 - 1:25 000)

The Australian Coastal Sediment Compartment data package consists of seven separate spatial data sets (2 point and 5 polygon) produced as a result of a 2012 technical workshop in which a panel of coastal science experts compartmentalised the Australian coastal zone. The three broad-scale polygon data layers - Coastal Realms, Regions and Divisions - capture high-level environmental attributes and information, and were developed as an informal hierarchy. These three data sets are supplied as they provide context and a logical sequence for the development of the compartments. With regards to spatial scale, a hierarchical listing for data sets is given below: - Coastal Realms (1:5 000 000) - Coastal Regions (1:1 000 000) - Coastal Divisions (1:250 000) - Primary Compartments and Points (1:250 000 - 1:100 000) - Secondary Compartments and Points (1:100 000 - 1:25 000) The Primary and Secondary Coastal Sediment Compartment (and Point) data sets represent a regional (1:250 000 - 1:100 000) and sub-regional (1:100 000 - 1:25 000) scale compartmentalisation of the Australian coastal zone into spatial units within (and between) which sediment movement processes are considered to be significant at scales relevant to coastal management. The Primary and Secondary Point data sets were generated and attributed using expert panel knowledge of coastal geomorphology and processes, and represent compartment boundaries along the coast at the respective scales. Environmental attributes used to determine the location of compartment (point) boundaries are given in priority order below. 1 - Gross lithological/geological changes (e.g. transition from sedimentary to igneous rocks). 2 - Geomorphic (topographic) features characterising a compartment boundary (often bedrock-controlled) (e.g. peninsulas, headlands, cliffs). 3 - Dominant landform types (e.g. large cuspate foreland, tombolos and extensive sandy beaches versus headland-bound pocket beaches). 4 - Changes in the orientation (aspect) of the shoreline. Once generated, the compartment boundary point data were used in conjunction with a number of other input data sets to generate the Primary and Secondary Compartments. Use Limitations: The Realm, Region and Division data sets are interim products used to establish a context for the development of the Primary and Secondary points and compartments. There is no formal topological relationship between the Realm, Region and Division data sets. An informal hierarchical (not topological) relationship does exist between the Primary compartments and the Divisions, as seen in the Primary compartment attribute field `ID_Primary. The Primary and Secondary compartments do share a formal topological relationship, and also a formal hierarchical relationships, as shown in the Secondary compartment attribute field `ID_Secondary. Primary compartments are intended to be representative at a spatial scale of 1:250 000 - 1:100 000 while secondary compartments are intended to be representative at scales from 1:100 000 - 1:25 000. IT IS IMPORTANT TO NOTE THAT THE COMPARTMENT POLYGON DATA IS NOT ATTRIBUTED WITH ENVIRONMENTAL DATA - ONLY THE PRIMARY AND SECONDARY POINT DATA SETS CONTAIN SUCH ATTRIBUTE DATA.

This point data set was created to identify locations on (or near) the Australian coastline which were considered to represent significant changes in key environmental attributes of the coast as they pertain to sediment movement in the coastal zone. This data was created during and subsequent to the technical workshop hosted by Geoscience Australia in Canberra from 16-18 October 2012. This workshop brought together the team of Australian coastal science experts listed below. - Prof. Bruce Thom - University of Sydney and the Wentworth Group - Prof. Andy Short - University of Sydney - Prof. Colin Woodroffe - University of Wollongong - Dr. Ian Eliot - University of Western Australia - Mr. Chris Sharples - University of Tasmania - Dr. Brendan Brooke - Geoscience Australia - Dr. Scott Nichol - Geoscience Australia The technical workshop had the goal of creating regional (primary) and sub-regional (secondary) scale coastal sediment compartments spatial zones (represented by polygons) within (or between) which sediment movement could be considered on scales and timeframes relevant to coastal management. The first step in this process involved the expert panel identifying and defining boundary points along the Australian coastline, after which the expert panel assigned relevant environmental attributes to each point. Following the development of the boundary points data set, breaklines representing the coast-perpendicular compartment boundaries were generated by extending a line from the defined offshore bathymetric contour to the defined onshore elevation contour. In every case a compartment breakline extends seaward and landward of its boundary point.

The Primary Coastal Sediment Compartment data set represents a regional-scale (1:250 000 - 1:100 000) compartmentalisation of the Australian coastal zone into spatial units within (and between) which sediment movement processes are considered to be significant at scales relevant to coastal management. The Primary and accompanying Secondary Coastal Sediment Compartment data sets were created by a panel of coastal science experts who developed a series of broader scale data sets (Coastal Realms, Regions and Divisions) in order to hierarchically subdivide the coastal zone on the basis of key environmental attributes. Once the regional (1:250 000) scale was reached expert knowledge of coastal geomorphology and processes was used to further refine the sub-division and create both the Primary and Secondary Sediment Compartment data sets. Environmental factors determining the occurrence and extents of these compartments include major geological structures, major geomorphic process boundaries, orientation of the coastline and recurring patterns of landform and geology - these attributes are given in priority order below. 1 - Gross lithological/geological changes (e.g. transition from sedimentary to igneous rocks). 2 - Geomorphic (topographic) features characterising a compartment boundary (often bedrock-controlled) (e.g. peninsulas, headlands, cliffs). 3 - Dominant landform types (e.g. large cuspate foreland, tombolos and extensive sandy beaches versus headland-bound pocket beaches). 4 - Changes in the orientation (aspect) of the shoreline.