Victoria Aquifer Framework - Lower Tertiary Basalts (a) - Depth to Basalt Surface (mAHD)

Surface of Lower Tertiary Basalts - LTBa - 112 -

The depth to the surface of the 'phase 1' basalts layer  is derived in relation to the Australian Height Datum in metres (mAHD).

The Victorian Aquifer Framework (VAF) was developed by the Department of Sustainability and Environment (DSE, now DELWP) to provide a consistent approach to defining, naming and numbering the commonly accepted aquifers, aquitards and geological layers that make up Victoria's groundwater systems. It is intended to assist in the sustainable management of groundwater resources in Victoria and provide the framework for mapping aquifers and aquitards across the State.

The 3D numeric surfaces (grids) of each layer have been styled and converted to GeoTIFF by the VVG project to optimise them for display and querying on the web. 

mAHD

Acronym for ‘metres above Australian Height Datum’.  The AHD is the 00.00m surface level established across Australia as a universal reference surface in 1971. When expressed as a negative (i.e.  -51 mAHD) it suggests a depth beneath the AHD, as in ’51 metres below the AHD’.  For further information:

http://www.ga.gov.au/scientific-topics/positioning-navigation/geodesy/datums-projections/australian-height-datum-ahd