Geochemistry of silicified wood and associated sediments, Petrified Forest National Park, Arizona
Geochemistry of silicified wood and associated sediments, Petrified Forest National Park, Arizona
复制标题
硅化木和相关沉积物的地球化学，亚利桑那州石化森林国家公园
DOI：
10.1016/0009-2541(79)90036-6
复制
发表时间：
1979
期刊：
影响因子：
3.9
通讯作者：
A. Sigleo
中科院分区：
文献类型：
--
作者：
A. Sigleo
亚利桑那州石化森林国家公园的硅化木和相关沉积物的沉积物矿物和微量元素含量表明，硅矿化发生在大多数溪流和地下水的成分范围内。硅化木周围的砂岩中含有高达15%的火山灰形成的自生蒙脱石，并显示出硅化木外部与二氧化硅共沉淀的证据。变价态元素的分布表明，木材的硅化是在缺氧的环境中进行的，如沼泽或滞水池塘的底泥。自生粘土矿物的总镧系元素浓度表明pH值为中等至弱酸性。没有证据表明溶液中存在碱性条件或特别高的二氧化硅浓度（> 140 mg/l）。
The sediment mineral and trace-element contents of silicified wood and associated sediments from the Petrified Forest National Park, Arizona, indicate that silica mineralization occurs within the compositional range of most stream and groundwaters. The sandstones surrounding the silicified wood contain up to 15% authigenic montmorillonite which formed from volcanic ash, and shows evidence of coprecipitation with silica in exterior parts of the silicified wood. The distribution of variable-valence elements indicates that the wood was silicified in an anoxic environment such as the bottom muds of a swamp or stagnant pond. The total lanthanide concentrations of authigenic clay minerals suggest an intermediate to slightly acidic pH. There is no evidence of alkaline conditions or exceptionally high silica concentrations (> 140 mg/l) in solution.