Abstract
This dataset was derived by the Bioregional Assessment Programme. The parent datasets are identified in the Lineage field in this metadata statement. The processes undertaken to produce this derived dataset are described in the History field in this metadata statement.
This dataset contains raster data layers estimating the rate of groundwater recharge for each hydrogeological formation in the Galilee subregion, by a chloride mass balance method. This method compares groundwater chloride concentrations (GUID: 6b1a0358-40d6-4bcf-b864-28cb2c823fd1) with chloride deposition in rainfall (GUID: c1649bd7-227f-41ff-9964-b55479bef640) for each hydrogeological formation. Cell values for each raster represent a rate in mm/year.
Purpose
This dataset is created to provide groundwater recharge volume estimates as an input into the Galilee groundwater model. For the purposes of the model, boundary extents used in the calculations are simplified and estimates should be used with caution if using for another purpose.
Dataset History
To create the recharge extent grids, the input data went through the following processes:
- Groundwater chloride concentration (Point data to raster)
Using the 'Topo to Raster' Tool in ArcCatalog, the input chloride data (GUID: 6b1a0358-40d6-4bcf-b864-28cb2c823fd1) for each hydrogeological formation's outcrop extent was converted into a raster dataset using the following parameters:
Feature layer - Input chemistry point data (GUID: 6b1a0358-40d6-4bcf-b864-28cb2c823fd1)
Field - Cl
Type - Point Elevation
Output cell size - 0.01
Output extent - Recharge outcrop (GUID: b0f0385e-c456-4fa4-9cdb-a5441cca407b)
Margin in cells - 20
Smallest z value to be used in interpolation - 10th percentile of Chloride Values
Largest z value to be used in interpolation - 90th percentile of Chloride Values
Drainage enforcement - NO_ENFORCE
Primary type of input data - SPOT
Maximum number of iterations - 40
- Output Chloride grid clipped to recharge boundary
Using the 'Extract by Mask' tool in ArcCatalog, the newly created chloride raster was clipped to the boundary of the recharge extent for each formation from the Galilee Groundwater Model, Hydrogeological Formation Recharge (Outcrop) Extents v01 (GUID: b0f0385e-c456-4fa4-9cdb-a5441cca407b) dataset.
- Chloride mass balance calculation between the groundwater chloride raster and the chloride deposition in rainfall raster (cl_deposition_final ascii file from the dataset - Australian 0.05º gridded chloride deposition v2 - GUID: c1649bd7-227f-41ff-9964-b55479bef640).
Using the 'Raster Calculator' Tool in Arc Catalogue the following statement was used to calculate the final recharge estimate for each formation: ([cl_deposition_final]" * 100) / [clipped groundwater chloride raster]
Dataset Citation
Bioregional Assessment Programme (2015) Galilee model recharge estimates: chloride mass balance v02. Bioregional Assessment Derived Dataset. Viewed 07 December 2018, http://data.bioregionalassessments.gov.au/dataset/d42a8497-9d67-42ad-9e7d-70a8d519875f.
Dataset Ancestors
