FrogTech, Permian Geology Base Faults - ARC

## **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\nThe layer in question describes faults interpreted to occur within the base of Permian geology within the Arckaringa Basin.\n\n## **Purpose** \n\nFault deformation was considered an important architectural feature of the Arckaringa basin to map, particularly with respect to the potential for inter-aquifer connectivity with other basins such as the Great Artesian Basin such faulting may engender.\n\n## **Dataset History** \n\nThe shapefile was developed by Frogtech in 2013. The generation of this and other interpretations developed by Frogtech followed this work flow pattern: 1.Complete all seismic and well interpretations after mistie analysis and fixes. 2.Define extent polygons for each unit using well data, surface geology polygons, seismic data and faults as constraints. This includes making detailed polygons of inclusions and exclusion areas for each grid to allow for erosional highs etc. 3.Define fault polygons in Kingdom for each surface where there is a mappable, significant offset on a horizon. 4.Create a test grid in twt using the gridding modules in Kingdom. The default gridding parameters used are 200m cell size, fault convergence (where faults are relevant) and moderate grid smoothng. 5.Review and interrogate the test map looking for grid artefacts. Review, check, adjust seismic interpretations as relevant. 6.Regrid. Iterate. 7.Once satisfied with the twt map, depth convert the relevant seismic horizon using the inbuilt Kingdom function to depth-convert by selected time-depth curve. After QA/QC we used the Cootanoorina-2 checkshot data to depth convert horizons in the north and east and the Arkeeta-1 checkshot data to depth convert horizons in the south. 8.Grid the horizon in the depth domain using the depth converted horizon and relevant depth-domain formation tops. 9.Review and assess the resultant draft depth structure map. 10.Remove grid artefacts and adjust interpretation as necessary. Regrid. Iterate. 11.Local smoothing of grids to create continuation of inferred troughs between control points and where first iteration isopachs show grid overlaps. Regrid. Iterate. 12.Create final maps in Kingdom. Export to ArcGIS. Create contours and apply consistent colour stretches to each map.\n\n## **Dataset Citation** \n\nSA Department of Environment, Water and Natural Resources (2015) FrogTech, Permian Geology Base Faults - ARC. Bioregional Assessment Source Dataset. Viewed 26 May 2016, http://data.bioregionalassessments.gov.au/dataset/ab5e2e15-3666-4ad3-a11d-b12e453990f3.## **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呈现。 本次涉及的图层描述了被解释为存在于阿卡林加盆地（Arckaringa Basin）二叠纪地质基底内的断层。 ## **目的** 断层变形被视为阿卡林加盆地（Arckaringa Basin）的重要构造特征，需将其作为重点填图对象，尤其是考虑到此类断层可能促成该盆地与大自流盆地（Great Artesian Basin）等其他盆地之间产生含水层间连通的潜力。 ## **数据集历史** 该形状文件（shapefile）由Frogtech于2013年开发。Frogtech开发的本数据集及其他解译成果均遵循以下工作流程： 1. 完成地震失配分析（mistie analysis）与修正后，完成所有地震与测井解译。 2. 以测井数据、地表地质多边形、地震数据及断层作为约束条件，为每个地层单元划定范围多边形。此步骤包括为每个网格生成详细的包含区与排除区多边形，以应对侵蚀高地等情况。 3. 在Kingdom软件中，针对存在可填图且层面上具有显著位移的每个界面定义断层多边形。 4. 使用Kingdom的网格化模块，在双程旅行时（two-way traveltime, TWT）域创建测试网格。本次采用的默认网格化参数为：200米网格单元尺寸、断层收敛（断层相关场景下）及适度网格平滑。 5. 审阅并核查测试图件，排查网格伪影（grid artefacts）。根据需要对地震解译成果进行复查、校验与调整。 6. 重新网格化，迭代优化。 7. 对双程旅行时图件满意后，使用Kingdom内置功能，通过选定的时深曲线将相关地震层面进行深度转换。在完成质量保证与质量控制（QA/QC）后，我们使用库塔纳里纳-2（Cootanoorina-2）检查测井数据对盆地北东部的层面进行深度转换，使用阿尔基塔-1（Arkeeta-1）检查测井数据对盆地南部的层面进行深度转换。 8. 使用已深度转换的层面及相关深度域地层顶界，在深度域对层面进行网格化。 9. 审阅并评估生成的深度构造草图。 10. 移除网格伪影，根据需要调整解译成果。重新网格化，迭代优化。 11. 对网格进行局部平滑，以在控制点之间延续推断的凹槽形态，并在首次迭代的等厚图（isopachs）显示网格重叠的区域进行处理。重新网格化，迭代优化。 12. 在Kingdom中生成最终图件，导出至ArcGIS，创建等高线并为每张图件应用统一的色彩拉伸效果。 ## **数据集引用** 南澳环境、水与自然资源部（SA Department of Environment, Water and Natural Resources）（2015）：FrogTech，《二叠纪地质基底断层——ARC》，生物区域评估源数据集。2016年5月26日查阅，http://data.bioregionalassessments.gov.au/dataset/ab5e2e15-3666-4ad3-a11d-b12e453990f3。