Namoi Leapfrog geological model

## **Abstract** \n\nThis dataset was supplied to the Bioregional Assessment Programme by a third party and is presented here as originally supplied. The metadata was not provided by the data supplier and has been compiled by the programme based on known details.\n\n\n\nThe Namoi Leapfrog geological model developed by CDM Smith for the future Santos' Gunnedah Coal Seam Gas Project (NTEC, 2013) using the software package Leapfrog Hydro™. The geological model was available to the Namoi subregion Assessment team and is considered to be fit for purpose as the basis for the Namoi geological model, developed for the Namoi BA programme.\n\n## **Dataset History** \n\nThis Namoi Leapfrog Model was created by CDM Smith and obtained from Santos Ltd for use in the Namoi Bioregional Assessment. \n\nThere is little documentation available for the geological model, however some is available as part of the Groundwater Impact Assessment for the Gunnedah Coal Seam Gas Project (NTEC, 2013). Each geological layer in the CDM Smith model is represented as a three-dimensional layer that can be continuous or discontinuous within the geological model domain. The thickness of layers and contact between the layers are modelled by the Leapfrog™ software based on interpolation and extrapolation of the input data and the types of stratigraphic relationships assigned in Leapfrog™. The model is discretised into 500 m x 500 m model cells. The thickness of each layer in each cell represents the mean formation thickness at that location. The model domain extends over approximately 53,200 km2 from the Hunter-Mooki Thrust Fault System in the east, to the extent of the Gunnedah Basin units in the south and north, which is outside the boundary of the Namoi subregion. The western boundary of the model domain is marked by the north-westerly groundwater flow direction in the Surat Basin.\n\nSources of data for the model include drilling logs from Santos and the NSW Department of Primary Industries Digital Imaging of Geological System (DIGS®) database, stratigraphic surfaces from the Upper and Lower Namoi groundwater models (McNeilage (2006) and Merrick (2001) respectively), the Gunnedah Bowen Study SEEBASE™ and Santos proprietary mapping of Gunnedah Basin formation tops and outcrop geology from geographic information systems (GIS). The ground surface elevation was determined using the Shuttle Radar Topography Mission (SRTM) 500 m digital elevation model (NTEC, 2013, p. 17, Table 2-1).\n\n## **Dataset Citation** \n\nGeoscience Australia (2016) Namoi Leapfrog geological model. Bioregional Assessment Source Dataset. Viewed 12 March 2019, http://data.bioregionalassessments.gov.au/dataset/26747362-8e20-49df-ab2c-918fba839aa4.

**摘要**
本数据集由第三方提供给生物区域评估计划（Bioregional Assessment Programme），此处按原始提交状态呈现。数据提供者未提供元数据，本计划基于已知细节自行编制了元数据。

本纳莫伊Leapfrog地质模型由CDM Smith为桑托斯（Santos）未来冈尼达煤层气项目（NTEC，2013）开发，采用Leapfrog Hydro™软件包构建。该地质模型已供纳莫伊次区域评估团队使用，且被认定符合使用要求，可作为为纳莫伊生物区域评估计划开发的纳莫伊地质模型的基础。

**数据集历史**
本纳莫伊Leapfrog模型由CDM Smith开发，并从桑托斯有限公司（Santos Ltd）获取，用于纳莫伊生物区域评估工作。

该地质模型的公开文档较少，但部分文档可在冈尼达煤层气项目地下水影响评估报告（NTEC，2013）中获取。CDM Smith开发的模型中，各地质层以三维图层形式呈现，可在地质模型域内呈连续或非连续分布。Leapfrog™软件基于输入数据的内插与外推，以及在Leapfrog™中指定的地层接触关系类型，对岩层厚度及层间接触关系进行建模。本模型被离散为500米×500米的模型网格单元，每个单元内各岩层的厚度代表该位置的地层平均厚度。模型域范围约为53200平方千米，东至亨特-穆基逆冲断裂系统，南、北延伸至冈尼达盆地地层分布边界，该范围超出了纳莫伊次区域的边界；模型域的西部边界以苏拉特盆地内的西北向地下水流向为界。

本模型的数据来源包括桑托斯提供的钻井日志，以及新南威尔士州第一产业部地质系统数字成像（DIGS®）数据库；还包括上下纳莫伊地下水模型的地层界面数据（分别对应McNeilage 2006年与Merrick 2001年的研究成果）、冈尼达-鲍恩研究的SEEBASE™数据集，以及桑托斯专有绘制的冈尼达盆地地层顶面图与露头地质的地理信息系统（GIS）数据。地表高程通过航天飞机雷达地形测绘任务（SRTM）500米数字高程模型确定（NTEC，2013，第17页，表2-1）。

**数据集引用**
澳大利亚地质调查局（2016）纳莫伊Leapfrog地质模型. 生物区域评估源数据集. 2019年3月12日查阅，http://data.bioregionalassessments.gov.au/dataset/26747362-8e20-49df-ab2c-918fba839aa4.