Boreholes (from Earth Resource's database)

Contains mineral, petroleum, coal &amp; groundwater boreholes. Minerals boreholes (and, to a lesser extent, petroleum wells) are actively maintained in the dataset. The custodial role for groundwater and coal boreholes is in the private sector, and these parts of the dataset are not actively maintained.

Mineral, petroleum and coal boreholes are updated on an irregular basis: Mineral borehole data are supplied by individual companies usually when their overlaying Exploration Licence expires; Coal borehole data have been updated from GHD Pty Ltd's (formerly GEO-ENG) data. Groundwater boreholes have not been updated since 1990 when the custodial role was given to Sinclair Knight Merz Pty Ltd (SKM) - refer to BORES100.

The origin of data varies considerably. Prior to 1980 borehole data was recorded by the Geological Survey of Victoria (GSV) on 1 inch:1 mile plans and hard-copy borehole records. This included data for water boreholes drilled by public and private sector, all boreholes drilled by GSV, petroleum wells, and some private-sector mineral exploration boreholes. In areas where drilling was of particularly high density, locations were recorded on these plans as a single point or as occurring within an outlined area.

The parish was traditionally used as the primary classifier for numbering boreholes. Some minor anomalies exist where a borehole and parish boundary may be on one side of a road or the other, or where parish boundaries have been moved.

In 1980 the location data was moved to 1:100,000 AMG plans. In the mid-1980s a program of electronic capture commenced. Borehole locations were digitised from the 1:100,000 plans with an accuracy of +/-300m. For the areas of high borehole density where boreholes were plotted on a single point, often only the first ten and last ten were recorded in the database. Boreholes whose parish was known but exact location was unknown were also recorded, but do not have a location.

Groundwater boreholes:
Extensive hydrological data was originally held by GSV, but these data are now held by SKM. 

Coal boreholes:
Location and lithological data for coal boreholes has been provided by Geo-Eng and the old State Electricity Commission of Victoria.

Mineral exploration boreholes:
The capture of mineral exploration borehole data from open-file exploration reports commenced in 2001 and will progressively cover the state over a number of years. The data are being captured at an whatever accuracy the source allows, typically between 20 and 250 m. Assay data have been consistently captured. Other downhole data, such as lithology, have not been consistently captured.

Tenement information for the small number of private-sector mineral exploration boreholes captured prior to 2001 was lost in the migration from the original VAX database to the current Ingres corporate database.

Heavy mineral sand exploration: complete coverage up for data up to April 2002; updates planned for late 2003.
Other mineral exploration: coverage as follows - 
 St Arnaud, Charlton, Wedderburn 1:100 000 mapsheets - 31 March, 2001;
 Dunolly, Rupanyup, Donald, Ararat, Grampians, Willaura 1:100 000 mapsheets -   30 August 2001;
 Warburton 1:250 000 mapsheet - 30 June 2002 (available mid-2003);
 Ballarat, Creswick, Skipton, Beaufort 1:100 000 mapsheets - 30 June 2002 (available mid-2003);
 Bendigo 1:250 000 - 31 October 2002 (available mid-2003)

Groundwater data can be obtained at the following site 
https://data.water.vic.gov.au/

Tags: Economy, Geoscientific information, Utilities communication
Organization: Department of Energy, Environment and Climate Action