I am aware of one species that occurs today, Miliammellus legis, which has a test of opaline silica. This species occurs at depths of approximately 4km (below the Carbonate Compensation Depth) in high latitude areas. It is similar in appearance to some miliolids, specifically species of Quinqueloculina, hence the family to which it belongs is termed the Silicoloculinidae.
Not only Foraminifera, all silicate skeletal floating miro-organismis can be accumulated below CCD which is 3-4 km depth, At that depth all carbonate skeletal disappear under high pressure water of ocean only siliceous skeletal can preserved to form siliceous ooze.
Most of the radiolaria, diatoms and some species of sponges at present day open ocean are made of silica. They are even found at depth of 4-5km covering extensive areas in abyssal plains for which the sediments found there are termed as siliceous ooze.
- Badges
- Science topic