WSeveral fossiliferous stratigraphic units in Madagascar have provided fossils, most notably the Maastrichtian Maevarano Formation and the Jurassic Isalo III Formation. The oldest fossil-bearing formations date to ages before the break-up of Madagascar from Africa and India; the units of the Sakoa Group are found in both India and Madagascar, while the Beaufort Group is shared with southern Africa.
WThe Ambolafotsy Formation is a Turonian aged geological formation in the Diego Basin of Antsiranana Province in Madagascar. It is a mostly terrestrial unit deposited during a marine regression close to the shoreline. The dinosaur Dahalokely has been discovered in the formation.
WThe Ankarafantsika Formation is a Late Cretaceous (Cenomanian) geologic formation of the Mahajanga Basin in the Boeny region of Madagascar, Africa. The fine-grained sandstones of the formation were deposited in a fluvial to lacustrine environment.
WThe Ankazomihaboka Formation is a Coniacian geologic formation in the Mahajanga Basin of northwestern Madagascar. The formation comprises claystones and sandstones deposited in a fluvial to lacustrine environment. The formation is overlain by the Marovoay Beds and overlies basalt.
WThe Beaufort Group is the third of the main subdivisions of the Karoo Supergroup in South Africa. It is composed of a lower Adelaide Subgroup and an upper Tarkastad Subgroup. It follows conformably after the Ecca Group and unconformably underlies the Stormberg Group. Based on stratigraphic position, lithostratigraphic and biostratigraphic correlations, palynological analyses, and other means of geological dating, the Beaufort Group rocks are considered to range between Middle Permian (Wordian) to Early Triassic (Anisian) in age.
WThe Bemaraha Formation is a Middle Jurassic geological formation of the Morondava Basin of Madagascar. The lime mudstones, grainstones and limestones of the formation were deposited in lagoonal and reefal environments. Fossils of groups of invertebrates and theropod and sauropod tracks have been found in the formation. The Sahalaly River tracksite yielded a single trackway belonging to a quadrupedal dinosaur, possibly a sauropod. Sauropod tracks are rare, making up as little as 1 percent of the present sample. The best-preserved tracks are assigned to the ichnogenus Kayentapus.
WThe Berivotra Formation is a Maastrichtian sedimentary formation of the Mahajanga Basin in Boeny, Madagascar. The claystones of the formation were deposited in a shallow marine environment. The Berivotra Formation overlies the fossil-rich Maevarano Formation, in which more fossils of Beelzebufo, also recovered from the Berivotra Formation, have been found. Many shark and ray teeth were collected by surface prospecting on outcrops of the Berivotra Formation, which is readily distinguished by its yellowish grey to pale olive colour, as opposed to the white and green fluvial sandstones that form the upper 15 to 20 metres of the underlying Maevarano Formation.
WThe Ecca Group is the second of the main subdivisions of the Karoo Supergroup of geological strata in southern Africa. It mainly follows conformably after the Dwyka Group in some sections, but in some localities overlying unconformably over much older basement rocks. It underlies the Beaufort Group in all known outcrops and exposures. Based on stratigraphic position, lithostratigraphic correlation, palynological analyses, and other means of geological dating, the Ecca Group ranges between Early to earliest Middle Permian in age.
WIsalo II, also known as the Makay Formation, is an informal Triassic geological unit in Madagascar.
WThe Isalo III Formation is a geological formation in Madagascar, off the eastern coast of Africa. It dates back to the Middle Jurassic. The use of the term "Isalo III" is somewhat controversial as the two prior units Isalo I and II are Triassic cross-bedded sandstone units that form a continuous depositional sequence, while the "Isalo III" sandstones are not part of the same depositional sequence, and were deposited considerably later. and are perhaps better treated as part of several separate formations. It is traditionally divided into two subunits the lower, Bajocian aged Isalo IIIa unit also known as the Beronono Formation and the upper, Bathonian aged Isalo IIIb unit also known as the Sakaraha Formation or Sakahara Formation. The Sakaraha Formation consists of sandstones, marls and carbonates and represents a coastal plain environment, and is laterally equivalent to the predominantly carbonate Bemaraha Formation, which represents a coastal barrier lagoon complex. The formation is found in the northwest and in the southeast of the country and has provided a variety of fossils.
WThe Kandreho Formation is an Early Jurassic geological formation of the Mahajanga Basin of Madagascar. The marly limestones of the formation were deposited in a subtidal lagoonal environment. The formation overlies the Bouleiceras and Spiriferina beds of the early Toarcian and has been correlated to the Marrat Formation of Saudi Arabia. Fossils of the marine crocodylian Andrianavoay as well as bivalves and the ammonite Nejdia have been found in the formation. The name Kandreho Formation was proposed by Geiger in 2004.
WThe Maevarano Formation is a Late Cretaceous sedimentary rock formation found in the Mahajanga Province of northwestern Madagascar. It is most likely Maastrichtian in age, and records a seasonal, semiarid environment with rivers that had greatly varying discharges. Notable animal fossils recovered include the theropod dinosaur Majungasaurus, the early bird Vorona, the flying dromaeosaur Rahonavis, the titanosaurian sauropod Rapetosaurus, and the giant frog Beelzebufo.