The Explanatory Notes System (ENS) is a digital database that contains detailed descriptions of rock units in Western Australia, with links to related tectonic units and geological events. ENS has replaced the older, printed Explanatory Notes, which were published for 1:100 000 and 1:250 000 scale geological maps. ENS is available through GeoVIEW.WA and is regularly updated with new data and interpretations, offering an up-to-date summary of the State’s geology.
Explanatory Notes are written for different types of geological units and events, including lithostratigraphic or rock units, tectonic units (broader geological features with a shared history) and geological events (e.g. the type of geological activity happening at different times).
These ENS reports are available through most geology layers in GeoVIEW.WA or by using the ENS Search tools. They can be generated by choosing a unit name, a general parameter (like age or rank), or an area of interest (by map name or polygon). If the unit selected is represented in GeoVIEW.WA, the layers it appears in will be highlighted in specific windows. For units not shown in GeoVIEW.WA, an All ENS Records window shows returns from the published ENS database.
ENS reports are provided for single (ENS Unit Report) or multiple units/events (ENS Overview report). Within each tectonic unit, overview reports and search returns provide a geologically sorted list, for example younger units are listed at the top and older units at the bottom. Tectonic units in Western Australia are ordered relative to each other in a single framework for the State, with ENS therefore providing the digital equivalent of a geological map legend.
Overview reports are available either as a table of contents or as fully expanded reports, with related units/events and references hyperlinked for convenience. All ENS reports can be saved as PDF, or MS Word and Excel documents.
ENS contains only current units; if a lithostratigraphic unit name cannot be found in ENS, please refer to Geoscience Australia’s Australian Stratigraphic Units Database for historical information on obsolete/superseded units.
ENS search and use help
ENS Help: searching for lithostratigraphic (lithstrat) units
