Biodiversity, Earth Sciences, Paleontology, Geochemistry, Taxa, Freshwater & Marine Ecology, Sedimentology, Sediments, Animal Systematics/Taxonomy/Biogeography, Succession, Plant Systematics/Taxonomy/Biogeography, Zonation, Northern Gondwana, Facies, Shallow-marine environment, Givetian/Frasnian boundary, Shales