Collaborative Research: The Evolution of Extremely Acid Lakes and Groundwaters in Western Australia

合作研究：西澳大利亚极酸湖泊和地下水的演变

• 批准号: 0719838
• 负责人: Francisca Oboh-Ikuenobe
• 金额: $ 16.7万
• 依托单位: Missouri University of Science and Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0719838&HistoricalAwards=false
• 关键词: Collaborative; Research; Evolution; Extremely; Acid

Acid and neutral saline lake and groundwater systems on the Yilgarn Craton in southern Western Australia represent a rare modern extreme environment type. These natural systems are characterized by waters with a pH range from 1.5 to 10.5 and diverse chemical composition, as well as by an unusual assemblage of depositional and diagenetic minerals, and novel extremophilic microorganisms. PIs will conduct a drilling project that will provide the first intact and complete samples of Quaternary and late Tertiary sediments from these extreme environments. Past surface and subsurface histories will be interpreted from sedimentological, mineralogical, and palynological studies of these cores. Temperatures, pHs, and chemical compositions of past surface water and groundwater will be determined by fluid inclusions in bedded and displacive halite and gypsum and stable isotopes in gypsum, alunite, and jarosite. Identification of palynomorphs and dating of organic-rich siliciclastics and diagenetic minerals will constrain ages. Any suspect microbial remains will be described and will undergo preliminary study. Data from ten cores from throughout the Yilgarn Craton will yield: (1) past depositional environments; (2) past lake water and groundwater chemistry and pH; and (3) past surface water temperatures, which serve as surface air temperature proxies, through the Quaternary for southern Western Australia. This research will document the evolution of these acid saline waters and their response to and from local, regional, and global geological processes. The recognition of past extreme environments in the rock record of Earth and Mars will be evaluated with this work. Finally, PIs will use these results to make predictions about the future evolution of acid saline waters in Western Australia, where it threatens farming, ranching, and even human habitation.This research is jointly funded with NSF's Office of International Science and Engineering.

西澳大利亚州南部Yilgarn河流域的酸性和中性咸水湖和地下水系统代表了一种罕见的现代极端环境类型。 这些自然系统的特点是沃茨的pH值范围为1.5至10.5，化学成分多样，沉积和成岩矿物的组合不同寻常，以及新的极端微生物。PI将进行一个钻探项目，该项目将提供来自这些极端环境的第四纪和晚第三纪沉积物的第一个完整和完整的样品。 过去的地表和地下历史将从这些岩心的沉积学、矿物学和孢粉学研究中得到解释。 过去地表水和地下水的温度、pH值和化学成分将由层状和置换型岩盐和石膏中的流体包裹体以及石膏、明矾石和黄钾铁矾中的稳定同位素确定。 孢粉化石的鉴定、富有机质硅质碎屑岩和成岩矿物的定年将制约成岩年龄。 任何可疑的微生物残留将被描述，并将进行初步研究。来自整个Yilgarn Nebon的10个岩心的数据将产生：（1）过去的沉积环境;（2）过去的湖水和地下水化学和pH值;（3）过去的地表水温度，作为地表空气温度的替代品，通过第四纪为西澳大利亚州南部。这项研究将记录这些酸性盐水沃茨的演变及其对当地、区域和全球地质过程的响应。 这项工作将评估对地球和火星岩石记录中过去极端环境的认识。 最后，PI将使用这些结果来预测西澳大利亚州酸性盐水沃茨的未来演变，在那里它威胁到农业，牧场，甚至人类居住。这项研究是与NSF的国际科学和工程办公室共同资助的。