Topic summary
Bioherm
Extracted from the Wikipedia article Reef knoll.
Reef knolls can be divided into bioherms and biostromes. A bioherm is a landform of organic sedimentary rock enclosed or surrounded by rock of different origin. A biostrome is a distinctly bedded or broadly lenticular sedimentary rock landform. Krumbein additionally used these terms to distinguish different shapes of stromatolites: "Distinctly bedded, widely extensive, blanketlike build-ups are biostromes. Nodular, biscuit-like, dome-shaped or columnar stromatolites are also referred to as bioherms".