These data represent the OZCHRON database of physical age determinations of Australian rocks, and the radiogenic isotope ratios used in determining the ages. OZCHRON datasets comprise bibliographic references, analytical data and pooled results for samples derived using the Rb-Sr, SHRIMP, U-Pb, and Sm-Nd age determination methods.

This data set is a classification of the Australian continent into 2-dimensional surface regions. A geological region is a relatively large geographical area with a cohesive, albeit in some cases complex, geological assemblage (Bain and Draper 1997, AGSO Bulletin 240); significantly different in overall geology from the adjoining regions, and differs from geological province in that it does not include depth or time dimensions. NOTE: Specialised Geographic Information System (GIS) software is required to view this data.

The Surface Geology of Australia 1:1M scale dataset (2012 edition) is a seamless national coverage of outcrop and surficial geology, compiled for use at or around 1:1 million scale. The data maps outcropping bedrock geology and unconsolidated or poorly consolidated regolith material covering bedrock. Geological units are represented as polygon and line geometries, and are attributed with information regarding stratigraphic nomenclature and hierarchy, age, lithology, and primary data source. The dataset also contains geological contacts, structural features such as faults and shears, and miscellaneous supporting lines like the boundaries of water and ice bodies. The 2012 dataset has been updated from the previous 2010 data by updating geological unit data to 2012 information in the Australian Stratigraphic Units Database (http://www.ga.gov.au/products-services/data-applications/reference-databases/stratigraphic-units.html), incorporating new published mapping in the Northern Territory and Queensland, and correcting errors or inconsistent data identified in the previous edition, particularly in the Phanerozoic geology of Western Australia. The attribute structure of the dataset has also been revised to be more compatible with the GeoSciML data standard, published by the IUGS Commission for Geoscience Information. The first edition of this national dataset was first released in 2008, with map data compiled largely from simplifying and edgematching existing 1:250 000 scale geological maps. Where these maps were not current, more recent source maps ranging in scale from 1:50 000 to 1:1 million were used. In some areas where the only available geological maps were old and poorly located, some repositioning of mapping using recent satellite imagery or geophysics was employed.

These data represent the OZCHRON database of age determinations on Australian rock samples as determined by the uranium-lead SHRIMP (Senstive High Resolution Ion MicroProbe) method. These data are a snapshot of the database at the "Ending-Date", although entry into the database is continuous. This product is intended as an interim form of data release while web-based accessibility to continually updated data is reformed during FY07-08.

The 1:2.5M scale geology of Australia data documents the distribution and age of major stratigraphic, intrusive and medium to high-grade metamorphic rock units of onshore Australia. This edition contains the same spatial content as the previous edition, but its geological attribute data is more complete than the 2010 edition. The dataset was compiled to use at scales between 1:2.5 million and 1:5 million inclusive. The units distinguished/mapped mainly represent stratigraphic supergroups, regional intrusive associations and regional metamorphic complexes. Groupings of Precambrian units in the time-space diagram are generally separated by major time breaks; Phanerozoic units are grouped according to stratigraphic age i.e. System/Period. The time-space diagram has the added benefit that it provides a summary of units currently included on the themes. The method used to distinguish sedimentary and many volcanic units varies for each geological eon as follows: - Cainozoic units are morphological units which emphasise the relationship of the sedimentary fill to the landscape. - Mesozoic units are regionally extensive to continent-wide time-rock units which emphasise the System of Period(s). - Paleozoic units are stratotectonic units that emphasise either the dominant System or Period(s) or the range of Periods. - Proterozoic units are commonly regional stratotectonic units - separated by major time breaks and split into the Paleoproterozoic, Mesoproterozoic and Neoproterozoic Eras - which are generally unique to each cratonic region. - Archaean units are regional lithological units grouped into broad time divisions. Metamorphic units are lithological units which emphasise the metamorphic facies and timing of the last major metamorphic event.

The Surface Geology of Australia data package includes: - Surface Geology of Australia, 1:1M scale (2012 edition) [GeoCat #74619 ] - Surface Geology of Australia, 1:2.5M scale (2012 edition) [GeoCat #73140 ], and - the national Geological Regions dataset [GeoCat #32366 ]. DVD data package of 3 national geological datasets