2.1.2.1 Methods

The primary aim of the compilation of the geological datasets described in this product is to inform the development of three-dimensional geological models of the Clarence-Moreton bioregion. In many traditional sedimentary basin geological and hydrogeological investigations, the primary aim of developing three-dimensional models is to characterise the aquifer geometry of deep sedimentary bedrock layers to facilitate the development of petroleum resources or characterise deep groundwater resources. Shallower aquifer systems such as alluvial systems or volcanic aquifers are often inadequately represented in these models or lumped together as ‘alluvium’ or ‘overburden’. To account for the fact that most water-dependent assets in the Clarence-Moreton bioregion are associated with shallow aquifers or surface water, three-dimensional geological models developed during this bioregional assessment aim to accurately describe the geometry of both shallow and deep aquifers in the Clarence-Moreton bioregion. In particular, the geological datasets and the three-dimensional geological models aim to characterise the geological contacts between the alluvium, the Main Range and Lamington volcanics and sedimentary bedrock. Understanding the geometry of these interfaces is critical to help with the conceptualisation of groundwater dynamics and surface water – groundwater interaction. It will also underpin the development of causal pathways that link coal resource developments to water-dependent assets described in companion product 2.3 for the Clarence‑Moreton bioregion (Raiber et al., 2016). Furthermore, it also provides the layer structure for a numerical groundwater flow model, which is developed to assess the potential impacts of CSG development on water resources in the Clarence‑Moreton bioregion (Cui et al., 2016).

The three-dimensional geological models developed as part of the Clarence‑Moreton Bioregional Assessment (the Assessment) are developed in GoCAD/SKUA (Paradigm Geophysical Pty Ltd®) and described in detail in companion product 2.3 for the Clarence‑Moreton bioregion (Raiber et al., 2016). They depict the main stratigraphic units of the Clarence‑Moreton bioregion (Figure 6), but do not represent variations in lithological composition (lithofacies or rock types). Furthermore, although the current three-dimensional geological models represent important structural features, fault displacements are not modelled in the current set of three-dimensional geological models (see Section 2.1.2.1.5 and Section 2.1.2.4).

Last updated:
11 July 2017
Thumbnail images of the Clarence-Moreton bioregion

Product Finalisation date

6 October 2016
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