Activity 1 - Chemistry, origins and hydrogeology of CSG water
The objective of Activity 1 of the Healthy HeadWaters Coal Seam Gas Water Feasibility Study is to collate, review and analyse existing data about the chemistry, origins and hydrogeology of coal seam gas (GSG) water to enable better understanding and monitoring of how CSG extraction may affect groundwater systems.
Activity 1 comprises three sub-activities:
- Activity 1.1 – Conceptualisation of the Walloon Coal Measures beneath the Condamine Alluvium
- Activity 1.2 – Spatial analysis of coal seam water chemistry
- Activity 1.3 – Scales of geological heterogeneity in the Walloon Coal Measures
Activity 1.1 – Conceptualisation of the Walloon Coal Measures beneath the Condamine Alluvium
3-D block model of the Walloon Coal Measures beneath the Condamine Alluvium
The objective of Activity 1.1 is to develop a hydrogeological conceptualisation—or conceptual model—of the Walloon Coal Measures where they underlie the Condamine Alluvlium.
This activity is complete.
Outcomes
Activity 1.1 undertook a comprehensive review of all existing data regarding the hydrogeology of the Condamine Alluvium and the underlying and flanking sections of the Walloon Coal Measures. It developed a new interpretation of these formations and assembled a three-dimensional block model. The findings of this activity provide an improved understanding of the structure of the Walloon Coal Measures and their relationship with the Condamine Alluvium, and also highlight priorities for future research. Outputs of this activity have been used by the former Queensland Water Commission in the development of a groundwater flow model to assess impacts of CSG water extraction in the Cumulative Management Area.
Final report
The Activity 1.1 Final report (PDF, 8.8M)* presents in detail the findings of the investigation. Due to its size, this report is also available in sections:
- Report text (PDF, 238K)*
- Figures (PDF, 4.4M)*
- Appendices (PDF, 4.2M)*
Other outputs
- Activity 1.1 summary (PDF, 849K)*
- Activity 1.1 poster (PDF, 3.7M)*
- Activity 1.1 information sheet (PDF, 118K)*
Activity 1.2 – Spatial analysis of coal seam water chemistry
Alkalinity levels in the Surat and Bowen basins
The objective of Activity 1.2 – Spatial analysis of coal seam water chemistry (PDF, 118K)* is to provide an improved understanding of the origins, recharge and flow regimes of coal seam waters in the Surat and Bowen basins, and an improved ability to identify interconnectivity between coal seams and other aquifers.
This activity is complete.
Outcomes
Activity 1.2 collated and analysed water quality data for coal seams and surrounding aquifers in the Surat and Bowen basins. The analysis consolidates existing knowledge about the mineralogical, hydrogeological and geochemical properties of these formations and provides new information about their distinguishing chemical features. The findings provide an enriched understanding of baseline conditions in these formations, and will be invaluable in the design and interpretation of future groundwater monitoring activities. A new database, which integrates all publicly available groundwater quality data for Queensland (as at March 2011) was constructed as part of this activity.
Final report
The Activity 1.2 Final report (PDF, 6.6M)* details the methods and results of the analyses performed in this investigation. The report can also be downloaded in separate sections:
- Report body (PDF, 3.2M)* - all sections except appendices
- Appendix 1 (PDF, 304K)* - Database development
- Appendices 2 to 6 (PDF, 1.0M)* - Water chemistry data and statistical analyses
- Appendix 7 (PDF, 2.1M)* - Hydrogeological figures
- Appendix 8 (PDF, 114K)* - Reactions affecting groundwater quality
Other outputs
- Activity 1.2 literature review report (PDF, 1.6M)*. This report reviews existing knowledge of the origins, recharge and flow regimes of coal seams and neighbouring aquifers in the Surat and Bowen Basins, and potential indicators of connectivity.
- Activity 1.2 summary (PDF, 2.0M)* (April 2011)
- Activity 1.2 poster (PDF, 1.5M)* (April 2011)
Activity 1.3 – Scales of geological heterogeneity in the Walloon Coal Measures
Vertical slices of a three-dimensional model of the Walloon Coal Measures
This activity will produce a geological model illustrating the general distribution of coals, sandstones and other materials within the Walloon Coal Measures in the eastern Surat Basin. A combination of deterministic and probabilistic modelling is being explored to improve understanding of the spatial heterogeneity of the Walloon Coal Measures. The output from these models can be used as input to future groundwater flow simulations that will assist in identifying the impacts of CSG extraction on surrounding aquifers.
Activity 1.3 is underway and is due for completion in early 2013.
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Last updated 8 January 2013
