An exploration trip in summer of 2011 turned into a forester's delight: Petrified pieces of sequoias or metasequoias are evidence of a different landscape and climate that existed in the now barren Shumagin Islands 20 - 25 million years ago.
Lush conifer forests of warmer climates in the Eocene to Oligocene ages were mostly silicified with volcanic ash of a high SiO2 content. The petrification process is not entirely understood. The Al2O3 and FE2O3 gives the rocks beautiful colors while the wood structure remains surprisingly authentic. However, it is difficult to say if the rock originating from trees were sequoias or the almost extinct metasequoias.
Lush conifer forests of warmer climates in the Eocene to Oligocene ages were mostly silicified with volcanic ash of a high SiO2 content. The petrification process is not entirely understood. The Al2O3 and FE2O3 gives the rocks beautiful colors while the wood structure remains surprisingly authentic. However, it is difficult to say if the rock originating from trees were sequoias or the almost extinct metasequoias.
