کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4689544 | 1636073 | 2013 | 12 صفحه PDF | دانلود رایگان |
Transitions in petrified wood samples from several Thailand–Myanmar sites included opal-A to opal-CT, opal-A to metastable β-crystobalite and reordered opal-CT → quartz. The moganite in the samples indicates a potential volcanic silica source for the wood petrifactions. Silica phase transitions evident under SEM include opal-A → opal-CT, opal-A → cuboid quartz (pseudocubic) and opal-CT → quartz. Certain stages of silica transformation and transition processes seem to overlap. Such overlapping results when lepisphere blades transform to the high crystallinity of prismatic quartz through a solid-state mechanism. The results provide some insights into the petrified wood genesis in the region. Thermal inputs into the silicification process may have pre-dated final burial of woods in flood deposits.
Journal: Sedimentary Geology - Volume 290, 15 May 2013, Pages 15–26