Here's a breakdown:
* Biogenic emphasizes the origin from living organisms.
* Organic highlights the presence of carbon-based compounds that were once part of the organisms.
Some common examples of biogenic sedimentary rocks include:
* Coal: Formed from the accumulation and compression of plant matter.
* Limestone: Often forms from the accumulation of shells and skeletons of marine organisms.
* Oil shale: Contains organic matter from algae and plankton.
* Chalk: Made from the skeletons of microscopic marine organisms called coccolithophores.
