Characterization of Herringbone Calcite from an Eocene Carbonate Platform, Egypt

埃及始新世碳酸盐台地人字形方解石的表征

• 批准号: 9972994
• 负责人: Dawn Sumner
• 金额: $ 11万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9972994&HistoricalAwards=false
• 关键词: Characterization; Herringbone; Calcite; Eocene; Carbonate

9972994Sumner Herringbone calcite, a distinctive calcite cement with macroscopic banding and specific crystallographic properties, may derive its distinctive morphology from the presence of Fe2+ or Mn2+ in the precipitating solution. Extremely well preserved herringbone calcite present in fissures and caves in a Middle Eocene carbonate platform, Egypt, will provide the opportunity to test previously proposed models for herringbone calcite precipitation based on Archean marine occurrences. If the conditions promoting herringbone calcite precipitation can be constrained, a better understanding of ancient ocean chemistry can be developed, and results will lead to insights into the fundamental processes controlling calcite crystal morphology. Thus, the research objectives for this project are to morphologically and geochemically characterize the Egyptian herringbonecalcite, and to use the results to constrain conditions promoting development of the herringbone calcite crystal texture.

9972994Sumner 人字形方解石是一种独特的方解石水泥，具有宏观条带和特定的晶体学特性，其独特的形态可能源于沉淀溶液中 Fe2+ 或 Mn2+ 的存在。 埃及中始新世碳酸盐台地的裂缝和洞穴中保存极其完好的人字形方解石，将为测试先前提出的基于太古宙海洋事件的人字形方解石沉淀模型提供机会。 如果能够限制促进人字形方解石沉淀的条件，就可以更好地了解古代海洋化学，其结果将有助于深入了解控制方解石晶体形态的基本过程。 因此，该项目的研究目标是从形态和地球化学角度表征埃及人字方解石，并利用研究结果来限制促进人字方解石晶体结构发展的条件。