Final report: National Marine Sediments Database and Seafloor Characteristics Project

The National Marine Sediments Database and Seafloor Characteristics project is a collaborative effort between the National Oceans Office and Geoscience Australia. The aims of the project included identification and collation of existing marine sediment data within the Australian Marine Jurisdiction, development and population of the MARS sediments database and mapping and analysis of sediment data for the Northern Planning Area and the Australian region to provide information for the National Benthic Marine Bioregionalisation. \nThe creation of the MARS database marks the transition to a new era of easy internet access to quantitative seafloor information. This is the first project to critically assess the quality and coverage of Australia's seafloor sediment data on a national scale. The initial phase of the project was the identification and collation of sediment data. At the completion of this phase, the MARS database contained about 25,000 samples for which 138,000 properties had been recorded. \nMaps of sediment properties were produced using validated quantitative data for two regions: the Northern Planning Area (NPA) and the whole of the Australian Marine Jurisdiction, excluding external territories. These maps show the distribution of measured grain size data (weight percent gravel, sand and mud), calculated mean grain size, as well as sediment classification based on the Folk scheme (Folk, 1954), and carbonate content. Mean grain size data for six of the marine domains were used to model sediment mobility in waters less than 300 m depth, using Geoscience Australia's GEOMAT package. The results of the modelling were produced as maps of tide and wave exceedance, and an energy regime regionalisation. \nAs a direct result of this project, the MARS database is now an important scientific and educational resource for those requiring detailed information on seafloor sediment characteristics within the Australian Marine Domain areas. The maps generated by this project show the level of detail and type of presentation possible when using quantitative data, but significant gaps in measured data coverage were also identified. Some 70% of the total marine domain remains unmapped in terms of measured sediment data. Much of this area is off the continental shelf, although gaps in the data coverage on the shelf are significant, particularly in the South-west and West-central Marine Domains\nStrategic directions for improving the data coverage include the analysis of existing sediment samples from Australian and overseas repositories. A valuable resource of seabed samples stored in Australia and overseas has been identified. These samples, if analysed, have the potential to double the existing overall measured data coverage for Australia's Marine Domains and would provide a cost-effective way of generating new data. The South-west Marine Domain would provide a useful pilot study to test the utility of analysing existing material.\n\nYou can also purchase hard copies of Geoscience Australia data and other products at http://www.ga.gov.au/products-services/how-to-order-products/sales-centre.html

国家海洋沉积物数据库与海底特征项目是国家海洋事务办公室（National Oceans Office）与澳大利亚地球科学局（Geoscience Australia）的合作科研项目。本项目目标包括：识别并整理澳大利亚海洋管辖海域内的现有海洋沉积物数据，开发并填充MARS沉积物数据库（MARS Sediments Database），针对北部规划区（Northern Planning Area，NPA）与澳大利亚全域海域开展沉积物数据制图与分析工作，为国家底栖海洋生物区划提供支撑数据。
MARS数据库的建成标志着定量海底信息迈入互联网便捷获取的新时代。本项目是首个在全国范围内严谨评估澳大利亚海底沉积物数据质量与覆盖范围的科研项目。项目初期阶段为沉积物数据的识别与整理，该阶段完成后，MARS数据库共收录约25000份沉积物样本，累计记录138000项沉积物属性参数。
研究团队针对两个区域制作了经验证的定量沉积物属性分布图：北部规划区（Northern Planning Area，NPA），以及不含海外领地的全澳大利亚海洋管辖海域。这些图谱展示了实测粒度数据（砾石、砂、泥的重量占比）、计算得到的平均粒径，以及基于福克分类方案（Folk scheme）的沉积物分类结果与碳酸盐含量（Folk, 1954）。
研究团队选取6个海洋域的平均粒径数据，借助澳大利亚地球科学局的GEOMAT软件包（GEOMAT package），对水深小于300米的海域开展沉积物活动性模拟。模拟结果以潮汐与波浪超越概率图、能量区划图的形式产出。
本项目的直接成果是，MARS数据库现已成为澳大利亚海洋域内亟需海底沉积物特征详细信息的科研与教育重要资源。本次项目生成的图谱不仅展示了使用定量数据可实现的细节精度与呈现形式，同时也识别出现有实测数据覆盖存在显著缺口：约70%的海洋域仍未完成沉积物实测数据填图。其中大部分缺口位于大陆架以外区域，但大陆架范围内的数据覆盖缺口同样不容忽视，尤其是西南及中西部海洋域。
提升数据覆盖范围的战略方向包括分析澳大利亚及海外馆藏的现有沉积物样本。研究团队已确认澳大利亚与海外保存有一批极具价值的海底样本资源，若对这些样本开展分析，有望将澳大利亚海洋域的实测数据覆盖范围提升一倍，同时可为获取新数据提供高性价比的途径。西南海洋域可作为试点研究区域，用以验证分析现有馆藏样本的实用性。
用户可通过http://www.ga.gov.au/products-services/how-to-order-products/sales-centre.html 购买澳大利亚地球科学局数据及其他产品的纸质版。