Stromatoporoid, Brachiopod and Anthozoan site in Hanh Phuc commune, Quang Uyen district. Coordinates X=649348; Y=2498589; Z=266m asl (1) and X=648129; Y=2499178; Z=295m asl (2). Stromatoporoid is found in limestone of Na Quan formation (D1-D2nq) (1) while brachiopod and anthozoan are found in clayish shale of Mia Le Formation (D1ml) (2).
– Brachiopod and Anthozoan site in the strongly deformed rocks of Mia Le Formation in Lang Mon commune, Nguyen Binh district (coordinates X=616924; Y=2506353; Z=302m asl). The fossils are seen dense within the bedding surfaces of clayish shale and limestone lenses.
The mentioned above fossils indicate a shallow marine environment. The sites also inform different karst landforms e.g. peak-cluster depression, fault-dominated karst blind valleys, and denudation-erosion landforms on terrigenous rocks.