GABATLAS - Cadna-owie - Hooray Aquifer Total Dissolved Solids map: Data

## **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\nData used to produce the predicted Total Dissolved Solids map for the Cadna-owie - Hooray Aquifer in the Hydrogeological Atlas of the Great Artesian Basin (Ransley et.al., 2014).\n\n\n\nThere are four layers in the Cadna-owie - Hooray Aquifer Total Dissolved Solids map data\n\n\n\nA. Location of hydrochemistry samples (Point data, Shapefile)\n\nB. Predicted Concentration (Filled contours , Shapefile)\n\nC. Predicted Concentration Contours (Contours, Shapefile)\n\nD. Prediction Standard Error (Filled contours , Shapefile)\n\n\n\nThe predicted values provide a regional based estimate and may be associated with considerable error. It is recommended that the predicted values are read together with the predicted error map, which provides an estimate of the absolute standard error associated with the predicted values at any point within the map.\n\n\n\nThe predicted standard error map provides an absolute standard error associated with the predicted values at any point within the map. Please note this is not a relative error map and the concentration of a parameter needs to be considered when interpreting the map. Predicted standard error values are low where the concentration is low and there is a high density of samples. Predicted standard errors values can be high where the concentration is high and there is moderate variability between nearby samples or where there is a paucity of data.\n\n\n\nConcentrations are Total Dissolved Solids mg/L.\n\n\n\nCoordinate system is Lambert conformal conic GDA 1994, with central meridian 134 degrees longitude, standard parallels at -18 and -36 degrees latitude.\n\n\n\nThe Cadna-owie - Hooray Aquifer Total Dissolved Solids map is one of 14 hydrochemistry maps for the Cadna-owie - Hooray Aquifer and 24 hydrochemistry maps in the Hydrogeological Atlas of the Great Artesian Basin (Ransley et. al., 2014). \n\n\n\nThis dataset and associated metadata can be obtained from www.ga.gov.au, using catalogue number 81693.\n\n\t\n\nReferences:\n\nHitchon, B. and Brulotte, M. (1994): Culling criteria for ‘standard’ formation water analyses; Applied Geochemistry, v. 9, p. 637–645\n\n\n\nRansley, T., Radke, B., Feitz, A., Kellett, J., Owens, R., Bell, J. and Stewart, G., 2014. Hydrogeological Atlas of the Great Artesian Basin. Geoscience Australia. Canberra. \\[available from www.ga.gov.au using catalogue number 79790\\]\n\n## **Dataset History** \n\nSOURCE DATA: \n\nData was obtained from a variety of sources, as listed below:\n\n1.\tWater quality data from the Queensland groundwater database, Department of Environment and Resource Management\n\n2.\tGeological Society of Queensland water chemistry database (1970s to 1980s). Muller, PJ, Dale, NM (1985) Storage System for Groundwater Data Held by the Geological Survey of Queensland. GSQ Record 1985/47. Queensland.\n\n3.\tGeoscience Australia GAB hydrochemistry dataset 1973-1997. Published in Radke BM, Ferguson J, Cresswell RG, Ransley TR and Habermehl MA (2000) Hydrochemistry and implied hydrodynamics of the Cadna-owie - Hooray Aquifer, Great Artesian Basin, Australia. Canberra, Bureau of Rural Sciences: xiv, 229p.\n\n4.\tFeitz, A.J., Ransley, T.R., Dunsmore, R., Kuske, T.J., Hodgkinson, J., Preda, M., Spulak, R., Dixon, O. & Draper, J., 2014. Geoscience Australia and Geological Survey of Queensland Surat and Bowen Basins Groundwater Surveys Hydrochemistry Dataset (2009-2011). Geoscience Australia, Canberra Australia\n\n5.\tWater quality data from the Office of Groundwater Impact Assessment, Department of Natural Resources and Mines, Queensland Government\n\n6.\tGeoscience Australia (2010) Hydrogeochemical collection. A compilation of quality controlled groundwater data taken from well completion reports from QLD and NSW. \n\n7.\tWater quality data from the Office of Groundwater Impact Assessment, Department of Natural Resources and Mines, Queensland Government\n\n\n\nBOUNDARIES:\n\nData covers the extent of the Cadna-owie-Hooray Aquifer and Equivalents as defined in Great Artesian Basin - Cadna-owie-Hooray Aquifer and Equivalents - Thickness and Extent dataset (Available from www.ga.gov.au using catalogue number 81678)\n\n\n\nMETHOD:\n\nGroundwater chemistry data was compiled from the data sources listed above. Data was imported into ESRI ArcGIS (ArcMap 10) as data point sets and used to create a predicted values surface using an ordinary kriging method within the Geostatistical Analyst extension. A log transform was applied to the Alkalinity, TDS, Na, SO4, Mg, Ca, K, F, Cl, Cl36 data prior to kriging. No transform was applied to the 13C, 18O, 2H, pH data prior to kriging. The geostatistical model was optimized using cross validation. The search neighbourhood was extended to a 1 degree radius, comprising of 4 sectors (N, S, E and W) with a minimum and maximum of 3 and 8 neighbours, respectively, per sector. The predicted values surface was exported to a vector format (Shapefile) and clipped to the aquifer boundaries.\n\n\n\nQAQC:\n\nPrior to data analysis all hydrochemistry data was assessed for reliability by Quality Assurance/Quality Control (QA/QC) procedures. A data audit and verification were performed using various quality checking procedures including identification and verification of outliers. \n\n\n\nThe ionic balance of each analysis was checked, and where the ionic charge balance differed by greater than 10%, these analyses were deemed unacceptable and were not considered for future analysis.\n\n\n\nData that passed the initial QA/QC procedures were checked against borehole construction and stratigraphic records to determine aquifer intercepts. Data were discarded in cases where there was no recorded location information or screen interval/depth information (to cross reference with borehole stratigraphy). One exception was chemistry data obtained from the NSW Governments Triton database. Groundwater chemistry data obtained from bore records in the Triton database that was also identified as GAB bores in the NSW Governments Pinneena database were assumed to be in the Pilliga Sandstone and were allocated to the Cadna-owie Hooray equivalent aquifer, despite many not recording depth information. \n\n\n\nGroundwater chemistry data was sourced from multiple studies, government databases, and companies. Many of the studies used sub-sets of the same data. All duplicates were removed before mapping and analysis. The differences between data sources had to be reconciled to ensure that maximum value of the data was retained and for errors in the transcription to be avoided. This precluded any automated processing system. Random checks were routinely made against the source data to ensure quality of the process. Some source data was in the form of thousands of consecutive rows and required python scripts or detailed table manipulations to correctly re-format the information and re-produce records with all the well data, its location and hydrochemical data for a particular sample date on one row in the collated Excel spreadsheet. Alkalinity measurements, in particular, were often reported differently between studies and even within the same database and required conversion to a common unit. All data before 1960 was discarded.\n\n\n\nThe study uses a data collection compiled from petroleum well completion reports from QLD and NSW. This data underwent a thorough QC process to ensure that drilling mud contaminated samples were excluded, based on the procedure described by Hitchon, B. & Brulotte, M. (1994). Less than 5% of the samples compiled passed the QC procedure, but these provide invaluable insight into the chemistry of very deep parts of the aquifers (typically 1 - 2km deep). \n\n\n\nWhere multiple samples have been taken at the same well, an average of the analyses was used in the kriging but outliers were removed. Outliers were identified by looking for large differences between predicted and measured samples. Excessively high values compared to predicted values and typical measurements at the same bore were discarded.\n\n## **Dataset Citation** \n\nGeoscience Australia (2015) GABATLAS - Cadna-owie - Hooray Aquifer Total Dissolved Solids map: Data. Bioregional Assessment Source Dataset. Viewed 11 April 2016, http://data.bioregionalassessments.gov.au/dataset/5044a067-35d1-4d6d-98a6-17974aa9226a.

## **摘要**
本数据集及其元数据声明由第三方提交至生物区域评估计划（Bioregional Assessment Programme），此处按原始提交版本原样呈现。

本数据集用于制作《大自流盆地水文地质图集》中卡德纳-奥维-胡里含水层（Cadna-owie - Hooray Aquifer）的总溶解固体（Total Dissolved Solids）预测分布图（Ransley等，2014）。

卡德纳-奥维-胡里含水层总溶解固体分布图数据包含4个图层：
A. 水文化学样品点位（点数据，Shapefile格式）
B. 预测浓度（填充等值线，Shapefile格式）
C. 预测浓度等值线（等值线，Shapefile格式）
D. 预测标准误差（填充等值线，Shapefile格式）

预测值为区域尺度估算结果，可能伴随较大误差。建议结合预测误差分布图解读预测值，该图可提供研究区内任意点位预测值对应的绝对标准误差估算值。

预测标准误差分布图可给出研究区内任意点位预测值对应的绝对标准误差。请注意，本图并非相对误差分布图，解读时需结合参数浓度值进行。当浓度较低且样品采样密度较高时，预测标准误差值较低；当浓度较高、邻近样品间变异程度中等或数据匮乏时，预测标准误差值可能较高。

浓度单位为总溶解固体（Total Dissolved Solids）毫克/升（mg/L）。

坐标系采用兰伯特正形圆锥投影GDA 1994，中央经线为东经134度，标准纬线为南纬18度和南纬36度。

卡德纳-奥维-胡里含水层总溶解固体分布图是《大自流盆地水文地质图集》中该含水层的14张水文化学图件之一，同时也是全图集的24张水文化学图件之一（Ransley等，2014）。

本数据集及相关元数据可通过澳大利亚地球科学局（Geoscience Australia）官网www.ga.gov.au获取，目录编号为81693。

### 参考文献
希奇顿（Hitchon, B.）与布鲁洛特（Brulotte, M.），1994年：《“标准”地层水分析的筛选标准》，《应用地球化学》，第9卷，第637–645页。
兰斯利（Ransley, T.）、雷德克（Radke, B.）、费茨（Feitz, A.）、凯利特（Kellett, J.）、欧文斯（Owens, R.）、贝尔（Bell, J.）与斯图尔特（Stewart, G.），2014年：《大自流盆地水文地质图集》，澳大利亚地球科学局，堪培拉。[可通过www.ga.gov.au获取，目录编号79790]

## **数据集历史**
### 源数据
数据源自以下多个渠道：
1. 昆士兰州环境与资源管理部（Department of Environment and Resource Management）昆士兰地下水数据库中的水质数据
2. 昆士兰地质学会水化学数据库（1970年代至1980年代）：穆勒（Muller, PJ）与戴尔（Dale, NM），1985年：《昆士兰地质调查局所持地下水数据的存储系统》，昆士兰地质调查局记录1985/47，昆士兰州。
3. 澳大利亚地球科学局大自流盆地水文化学数据集（1973-1997年）：收录于雷德克（Radke BM）、弗格森（Ferguson J）、克雷斯韦尔（Cresswell RG）、兰斯利（Ransley TR）与哈伯梅尔（Habermehl MA），2000年：《澳大利亚大自流盆地卡德纳-奥维-胡里含水层的水化学特征与隐含水动力学》，堪培拉，农村科学局，共xiv页、229页。
4. 费茨（Feitz, A.J.）、兰斯利（Ransley, T.R.）、邓斯莫尔（Dunsmore, R.）、库斯克（Kuske, T.J.）、霍奇金森（Hodgkinson, J.）、普雷达（Preda, M.）、斯普尔拉克（Spulak, R.）、迪克森（Dixon, O.）与德雷珀（Draper, J.），2014年：《澳大利亚地球科学局与昆士兰地质调查局苏拉特和 Bowen 盆地地下水调查水化学数据集（2009-2011年）》，澳大利亚地球科学局，澳大利亚堪培拉。
5. 昆士兰州政府自然资源与矿产部地下水影响评估办公室的水质数据
6. 澳大利亚地球科学局，2010年：水文地球化学数据集。该数据集整合了从昆士兰州和新南威尔士州钻井完工报告中提取的经过质量控制的地下水数据。
7. 昆士兰州政府自然资源与矿产部地下水影响评估办公室的水质数据

### 覆盖范围
本数据集覆盖范围与《大自流盆地——卡德纳-奥维-胡里含水层及等效含水层——厚度与分布范围》数据集所定义的卡德纳-奥维-胡里含水层及等效含水层范围一致（可通过www.ga.gov.au获取，目录编号81678）。

### 制图方法
地下水化学数据整合自上述数据源。将数据以点数据集形式导入ESRI ArcGIS（ArcMap 10），并通过地理统计分析扩展模块中的普通克里金法生成预测值表面。在克里金插值前，对碱度、总溶解固体、钠、硫酸盐、镁、钙、钾、氟、氯、氯36等数据进行对数变换；而对碳13、氧18、氢2、pH值等数据未进行变换。通过交叉验证优化地统计模型，搜索邻域扩展至1度半径范围，分为北、南、东、西4个扇区，每个扇区的最小邻域点数为3，最大为8。将预测值表面导出为矢量格式（Shapefile），并裁剪至含水层边界范围。

### 质量保证与质量控制（QA/QC）
数据分析前，所有水文化学数据均通过质量保证与质量控制（QA/QC）流程评估可靠性。采用多种质量检查流程开展数据审核与验证，包括异常值识别与核查。

对每份分析数据的离子平衡进行检查，若离子电荷平衡偏差超过10%，则判定该分析数据不可接受，不纳入后续分析。

通过初始QA/QC流程的数据，将结合钻孔结构与地层记录核查以确定含水层截取深度。若无点位记录或滤水管段/深度信息（无法与钻孔地层学交叉验证），则剔除该数据。唯一例外为新南威尔士州政府Triton数据库中的化学数据：从Triton数据库钻孔记录中获取的、且在新南威尔士州政府Pinneena数据库中被标记为大自流盆地钻孔的地下水化学数据，尽管多数未记录深度信息，仍被假定属于皮利加砂岩含水层，并划归至卡德纳-奥维-胡里等效含水层。

地下水化学数据源自多项研究、政府数据库与企业数据源，其中多项研究使用了同一数据集的子集。制图与分析前已剔除所有重复数据。需协调不同数据源间的差异，以确保最大化保留数据价值并避免转录误差，因此无法采用自动化处理流程。常规需随机核查原始数据以保障流程质量。部分原始数据以数千行连续记录形式存在，需借助Python脚本或精细化表格操作进行格式重构，将单条样品记录的全部井信息、点位信息与特定采样日期的水化学数据整合至合并后的Excel表格单一行中。尤为特殊的是，碱度测量值在不同研究甚至同一数据库内的报告形式存在差异，需统一转换为标准单位。1960年之前的所有数据均予以剔除。

本研究使用的数据集整合自昆士兰州与新南威尔士州的石油钻井完工报告。依据希奇顿与布鲁洛特（1994年）提出的流程，对该数据开展了严格的QC流程，以剔除受钻井泥浆污染的样品。最终仅不足5%的汇编样品通过QC流程，但这些数据为了解含水层极深部（通常1~2公里）的水化学特征提供了宝贵信息。

若同一钻孔采集了多份样品，则在克里金插值中使用分析结果的平均值，但需剔除异常值。异常值通过预测值与实测值间的显著偏差识别，与同一钻孔的预测值和典型实测值相比过高的异常值将被剔除。

## **数据集引用**
澳大利亚地球科学局，2015年：《GABATLAS——卡德纳-奥维-胡里含水层总溶解固体分布图：数据》，生物区域评估源数据集，2016年4月11日查阅，http://data.bioregionalassessments.gov.au/dataset/5044a067-35d1-4d6d-98a6-17974aa9226a。