Great Artesian Basin, Westbourne Aquitard - thickness and extent

## **Abstract** \n\nThis dataset and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are presented here as originally supplied.\n\n\n\nThe Westbourne Aquitard - Thickness and Extent data set, is one of a set that represents the hydrostratigraphic units of the Great Artesian Basin, which include five major aquifers, four intervening aquitards, and the Cenozoic cover to the GAB. The datasets have been derived from the lithostratigraphic intercepts in drillhole data from petroleum exploration wells, water bores, and stratigraphic wells. Seismic correlation and assessment of hydrogeological character based on electrofacies have not been used. The working datasest for this study has been derived primarily from the following databases: 1. PEPS-SA (Petroleum Exploration and Production System - South Australia) (Department of Primary Industries and Regions SA, 2011) 2. WaterConnect Groundwater database (Govt. of SA, 2011) 3. QPED (Queensland Petroleum exploration database) (Geological Survey of Queensland, 2010). 4. GABLOG (Great Artesian Basin Well Log Dataset) (Habermehl, 2001) 5. Additional supplementary information was derived from published reports listed in the following section. This is a regional interpretation for mapping at approximately 1:1 000 000 to produce a broad scale overview, and examination of small areas by collecting extra data is most likely to produce results that differ from this regional interpretation. Associated report reference: Ransley, T., Radke, B., Feitz, A., Kellett, J., Owens, R., Bell, J. and Stewart, G., 2015. Hydrogeological Atlas the Great Artesian Basin. Geoscience Australia. Canberra. \\[available from www.ga.gov.au using catalogue number 79790\\] References - main data sources - Department of Primary Industries and Regions SA (2011). Petroleum Exploration and Production System - South Australia (PEPS-SA). Version 2011-06-15. Retrieved from http://www.pir.sa.gov.au/petroleum/access_to_data/peps-sa_database - Geological Survey of Queensland (2010). Queensland Petroleum Exploration Data (QPED) database. Retrieved 25 September 2011, from http://mines.industry.qld.gov.au/geoscience/geoscience-wireline-log-data.htm. - Govt. of South Australia (2011). WaterConnect Groundwater database \\[available at https://www.waterconnect.sa.gov.au\\]. - Geoscience Australia, 2013. Mesozoic Geology of the Carpentaria and Laura Basins. Scale 1:6000000. Geoscience Australia, Canberra. \\[available from www.ga.gov.au using catalogue number 75840\\] - Habermehl, M. A. (2001). Wire-line logged water bores in the Great Artesian Basin, Australia - digital data of logs and water bore data acquired by AGSO. Australian Geological Survey Organisation Bulletin 245. Canberra, Bureau of Rural Sciences: ix, 98 p.\n\n## **Dataset History** \n\nMETHOD: Formation Extent Extents were based on drillhole data from GABLOG (Habermehl, M. A., 2001), PEPS-SA (Department of Primary Industries and Regions SA, 2011), QPED (Geological Survey of Queensland, 2010) and WaterConnect Groundwater database (Govt. of SA, 2011). Extent lines were adjusted to envelop all intercepts of the Hydrostratigraphic unit. This produced some varied and irregular shapes, some patchy regions, and required some interpretation to establish the most likely extent boundary. Outcrop Extent Outcrop extents sourced from Hydrogeology of the Great Artesian Basin Australia (Habermehl & Lau, 1997) for the Eromanga and Surat sub-basins, and from Mesozoic Geology of the Carpentaria and Laura Basins (Geoscience Australia, 2013) for the Carpentaria Basin. Isopach Raster Source point thickness values calculated from drillhole intercepts were extrapolated using the ESRI ANUDEM Topo-To-Raster surface modeller. Zero thickness constraints were applied at the known extent of the aquifer/aquitard, except in cases where the formation extends beyond the GAB boundary (for example the Precipice formation on the eastern side of the GAB, where the formation is quite thick and is exposed as a cliff). In these cases, constraints were not applied and the software was allowed to model a thickness right up to the GAB boundary. Resulting grids were modified using the ESRI Grid Calculator to set the minimum thickness to 0, and clipped to the aquifer/aquitard extent. Isopach Contours Isopach contours were calculated from the Westbourne Aquitard thickness grid (generated from drillhole intercepts in Clarence-Moreton from OBrien (2011)) using the ESRI Contour Tool. These were calculated at 50m intervals. In most cases the zero contour lines generated by the tool were replaced by the extent of the aquifer due to the erratic nature of the generated lines. In cases where the aquifer/aquitard is thick at the extent, the zero isoline is outside the extent and is not mapped in that area. Isopachs were clipped to the aquifer/aquitard extent. Data Point Locations Data Point Locations have been derived from the bore hole data collected for this project. Only the location has been included. SOFTWARE: All modifications/edits and geoprocessing were performed using ESRI ArcGIS 10 software.\n\n## **Dataset Citation** \n\nGeoscience Australia (2015) Great Artesian Basin, Westbourne Aquitard - thickness and extent. Bioregional Assessment Source Dataset. Viewed 07 December 2018, http://data.bioregionalassessments.gov.au/dataset/cba1a795-5502-44f4-80e8-d03bd4f5ae5a.

## **摘要**

本数据集及其元数据声明由第三方提供给生物区域评估计划（Bioregional Assessment Programme），此处按原始提交版本呈现。

西本迪隔水层（Westbourne Aquitard）厚度与分布范围数据集，是代表大自流盆地（Great Artesian Basin, GAB）水文地层单元的数据集之一，该套单元包含5个主要含水层、4个相邻隔水层以及覆盖于大自流盆地之上的新生代地层。本数据集源自石油勘探井、水井以及地层井的钻孔数据中的岩石地层截获数据，未采用地震对比以及基于电相的水文地质特征评估方法。本研究的工作数据集主要源自以下数据库：1. 南澳州石油勘探与生产系统（PEPS-SA, Petroleum Exploration and Production System - South Australia）（南澳州第一产业与区域部，2011年）；2. 水连接地下水数据库（WaterConnect Groundwater database，南澳州政府，2011年）；3. 昆士兰州石油勘探数据库（QPED, Queensland Petroleum exploration database）（昆士兰州地质调查局，2010年）；4. 大自流盆地测井数据集（GABLOG, Great Artesian Basin Well Log Dataset）（哈伯迈尔，2001年）；5. 补充信息源自下文列出的已发表报告。本研究为约1:1000000比例尺制图的区域解译，旨在生成宏观概览，若通过收集额外数据对小区域开展核查，所得结果大概率与该区域解译结果存在差异。相关报告参考文献：兰斯利，T.、拉德克，B.、费茨，A.、凯尔蒂，J.、欧文斯，R.、贝尔，J.与斯图尔特，G.，2015年。《大自流盆地水文地质图集》。澳大利亚地质科学局，堪培拉。[可从澳大利亚地质科学局官网www.ga.gov.au获取，目录号79790]

主要数据来源参考文献：
- 南澳州第一产业与区域部（2011年）。《南澳州石油勘探与生产系统（PEPS-SA）》，版本2011-06-15。检索自http://www.pir.sa.gov.au/petroleum/access_to_data/peps-sa_database
- 昆士兰州地质调查局（2010年）。《昆士兰州石油勘探数据（QPED）数据库》，2011年9月25日检索自http://mines.industry.qld.gov.au/geoscience/geoscience-wireline-log-data.htm
- 南澳州政府（2011年）。《水连接地下水数据库》[可从https://www.waterconnect.sa.gov.au获取]
- 澳大利亚地质科学局，2013年。《卡奔塔利亚与劳拉盆地中生代地质》，比例尺1:6000000。澳大利亚地质科学局，堪培拉。[可从www.ga.gov.au获取，目录号75840]
- 哈伯迈尔，M. A.（2001年）。《澳大利亚大自流盆地测井水井——由澳大利亚地质调查局（AGSO）采集的测井与水井数据数字化数据集》。澳大利亚地质调查局公报245。堪培拉，农村事务局：ix, 98 p.

## **数据集历史**

### 方法：
1. **分布范围解译**：分布范围基于GABLOG（哈伯迈尔，2001年）、PEPS-SA（南澳州第一产业与区域部，2011年）、QPED（昆士兰州地质调查局，2010年）以及WaterConnect地下水数据库（南澳州政府，2011年）中的钻孔数据确定。分布范围线经调整后覆盖该水文地层单元的所有钻孔截获点，由此生成了形态各异且不规则的形状，部分区域存在斑块状分布，因此需要通过解译确定最合理的分布边界。
2. **露头范围**：露头范围数据源自《澳大利亚大自流盆地水文地质》（哈伯迈尔与劳，1997年）（针对艾罗曼加与瑟拉特次盆地），以及《卡奔塔利亚与劳拉盆地中生代地质》（澳大利亚地质科学局，2013年）（针对卡奔塔利亚盆地）。
3. **等厚栅格数据**：基于钻孔截获点计算的源点厚度值，通过ESRI ANUDEM地形转栅格表面建模工具进行外推。在已知含水层/隔水层的分布范围内应用零厚度约束，但当地层延伸至大自流盆地边界以外时除外（例如大自流盆地东侧的普雷西皮斯地层，该地层厚度较大且裸露形成悬崖）。此类情况不应用约束条件，允许软件建模至大自流盆地边界。生成的栅格经ESRI栅格计算器修正，将最小厚度设为0，并裁剪至含水层/隔水层的分布范围。
4. **等厚等值线**：等厚等值线基于西本迪隔水层厚度栅格（由克莱伦斯-莫尔顿地区的钻孔截获点生成，数据源自奥布莱恩，2011年），通过ESRI等值线工具计算得出，等值线间距为50米。多数情况下，由于工具生成的零等值线存在不规则性，将其替换为含水层的分布范围。当含水层/隔水层在分布边界处厚度较大时，零等值线位于分布范围之外，因此不会在该区域进行制图。等厚等值线被裁剪至含水层/隔水层的分布范围。
5. **数据点位置**：数据点位置源自本项目采集的钻孔数据，仅保留点位坐标信息。

**软件**：所有修改、编辑与地理处理操作均使用ESRI ArcGIS 10软件完成。

## **数据集引用**

澳大利亚地质科学局（2015年）。《大自流盆地：西本迪隔水层——厚度与分布范围》，生物区域评估源数据集。2018年12月7日查阅，http://data.bioregionalassessments.gov.au/dataset/cba1a795-5502-44f4-80e8-d03bd4f5ae5a。