• The outcrop is situated in a small riverbed, which was dry in March 2012, 2

•km north of the town of Tsuno (Tsuno district, Kochi prefecture). Reefal limestone blocks of tens of centimeters to few meters are embedded in green volcaniclastic and sparry calcite matrix. All of the collected blocks correspond to coral-sponge boundstone with minor amounts of microproblematica and algae. The preservation is good despite minor silicification. The taxonomic diversity is high (25 species were determined). The primary framebuilders (mainly corals and sponges) are encrusted by several generations of microbial crust and sessile organisms. There are a few voids with isopachous cements, and peloid-microproblematica grainstone-pack stone sediment and peloidal-clotted micrite fill the interstices between the skeletal elements

• reef limestone blocks