Siliceous soils are formed from rocks that have silica (SiO2) as a principal constituent.
The parent material of siliceous soils may include quartz sands, chert, quartzite, quartz reefs, granite, rhyolite, ademellite, dellenite, quartz sandstone, quartz siltstone, siliceous tuff, among others.
[1] These parent materials sometimes originate from silica-secreting organisms such as radiolarians, diatoms, or some types of sponges.
[2] Soils high in siliceous parent material typically have:[1] Siliceous soils in vineyard soils have been linked to larger grapes with increased tannin content.
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