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: 0719822
• 负责人: Kathleen Benison
• 金额: $ 27.3万
• 依托单位: Central Michigan University
• 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=0719822&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.

西澳大利亚南部Yilgarn Craton上的酸和中性盐湖和地下水系统代表了一种罕见的现代极端环境类型。 这些天然系统的特征是pH值范围为1.5至10.5，并且具有多样的化学成分，以及沉积和成岩矿物质的异常组合以及新型的过性微生物。 PI将进行一个钻井项目，该项目将提供这些极端环境中第四次和晚期沉积物的完整样本。 过去的表面和地下历史将从这些核心的沉积学，矿物学和孢子学研究来解释。 过去的地表水和地下水的温度，pH和化学成分将由床单，位移卤石和石膏的流体夹杂物确定，石膏，铝石和jarosite的稳定同位素。 识别palynomorphs和有机富含有机硅和成岩矿物的日期将限制年龄。 任何可疑的微生物遗体将被描述，并将接受初步研究。来自整个Yilgarn Craton的十个核心的数据将产生：（1）过去的沉积环境； （2）过去的湖水和地下水化学和pH； （3）通过西澳大利亚南部的第四纪，过去的地表水温是表面空气温度代理。这项研究将记录这些酸盐水的演变及其对本地，区域和全球地质过程的反应。 这项工作将评估地球和火星岩石记录中过去极端环境的认识。 最后，PIS将使用这些结果来预测西澳大利亚州酸盐水的未来演变，它威胁到耕作，牧场甚至人类居住。