The Old Red Sandstone is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the northeastern seaboard of North America. It also extends northwards into Greenland and Svalbard. These areas were a part of the ancient continent of Euramerica/Laurussia. In Britain it is a lithostratigraphic unit to which stratigraphers accord supergroup status and which is of considerable importance to early paleontology. For convenience the short version of the term, ORS is often used in literature on the subject. The term was coined to distinguish the sequence from the younger New Red Sandstone which also occurs widely throughout Britain.
Pterygotus is a genus of giant predatory eurypterid, a group of extinct aquatic arthropods. Fossils of Pterygotus have been discovered in deposits ranging in age from Middle Silurian to Late Devonian, and have been referred to several different species. Fossils have been recovered from four continents; Australia, Europe, North America and South America, which indicates that Pterygotus might have had a nearly cosmopolitan (worldwide) distribution. The type species, P. anglicus, was described by Swiss naturalist Louis Agassiz in 1839, who gave it the name Pterygotus, meaning "winged one". Agassiz mistakenly believed the remains were of a giant fish; he would only realize the mistake five years later in 1844.
Slimonia is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Slimonia have been discovered in deposits of Silurian age in South America and Europe. Classified as part of the family Slimonidae alongside the related Salteropterus, the genus contains three valid species, S. acuminata from Lesmahagow, Scotland, S. boliviana from Cochabamba, Bolivia and S. dubia from the Pentland Hills of Scotland and one dubious species, S. stylops, from Herefordshire, England. The generic name is derived from and honors Robert Slimon, a fossil collector and surgeon from Lesmahagow.
Acutiramus is a genus of giant predatory eurypterid, an extinct group of aquatic arthropods. Fossils of Acutiramus have been discovered in deposits of Late Silurian to Early Devonian age. Seven species have been described, five from North America and two from the Czech Republic. The generic name derives from Latin acuto and Latin ramus ("branch"), referring to the acute angle of the final tooth of the claws relative to the rest of the claw.
Nanahughmilleria is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Nanahughmilleria have been discovered in deposits of Devonian and Silurian age in the United States, Norway, Russia, England and Scotland, and have been referred to several different species.
Erettopterus is a genus of large predatory eurypterid, an extinct group of aquatic arthropods. Fossils of Erettopterus have been discovered in deposits ranging from Early Silurian to the Early Devonian, and have been referred to several different species. Fossils have been recovered from two continents; Europe and North America. The genus name is composed by the Ancient Greek words ἐρέττω (eréttō), which means "rower", and πτερόν (pterón), which means "wing", and therefore, "rower wing".
The Beacon Supergroup is a geological formation exposed in Antarctica and deposited from the Devonian to the Triassic. The unit was originally described as either a formation or sandstone, and upgraded to group and supergroup as time passed. It contains a sandy member known as the Beacon Heights Orthoquartzite.
Fujian is a south eastern coastal province of China. The eastern half of the province is largely covered by Jurassic Period acid volcanic rocks and Cretaceous tuffaceous sandstone. However, there are rocks of a variety of ages including the oldest around 1800 Ma. The deposits from the Triassic are predominantly on land, whereas the older ones are marine sediments.
The Trout Valley Formation is a geologic formation in Maine. It preserves fossils dating back to the Devonian period.
The Sundvollen Formation is a geologic formation cropping out along the northern and eastern shores of Steinsfjorden, Oslo Region, Norway. It preserves fossils dating back to the Gorstian to Ludfordian stages of the Late Silurian period.
Santa Juana Formation a Late Triassic sedimentary rock formation near Santa Juana in the lower course of the Biobío River in south-central Chile. Lithologies range from conglomerate sandstone, arkosic sandstone, siltstone and mudstone.
The geology of Yukon includes sections of ancient Precambrian Proterozoic rock from the western edge of the proto-North American continent Laurentia, with several different island arc terranes added through the Paleozoic, Mesozoic and Cenozoic, driving volcanism, pluton formation and sedimentation.
The Kirusillas Formation is a Homerian geologic formation of central Bolivia. The formation comprises black shales, overlies the Llallagua Formation and is overlain by the Pampa and Guayabillas Formations. The Kirusillas Formation is laterally equivalent to the Lipeón Formation. The formation is a potential source rock for shale oil and shale gas.
The Bertie Group or Bertie Limestone, also referred to as the Bertie Dolomite and the Bertie Formation, is an upper Silurian geologic group and Lagerstätte in southern Ontario, Canada, and western New York State, United States. Details of the type locality and of stratigraphic nomenclature for this unit as used by the U.S. Geological Survey are available on-line at the National Geologic Map Database. The formation comprises dolomites, limestones and shales and reaches a thickness of 495 feet (151 m) in the subsurface, while in outcrop the group can be 60 feet (18 m) thick.
The Lipeón Formation is a Telychian to Pridoli geologic formation of southern Bolivia and northwestern Argentina. The formation comprises sandstones and siltstones. Plant fossils comprising rhyniophytes are scattered throughout, with some abundant concentrations on micaceous bedding plains. The fossil flora is the oldest of South America. Also present were quite diverse small, irregularly branching fragments possibly the tips of algae such as Buthotrephis or Hungerfordia.
The Fish Bed Formation is a geologic formation in Scotland, United Kingdom. The fluvial to lacustrine sandstones, shales, siltstones and conglomerates preserve flora, arthropods, among which eurypterids, invertebrates and early fish fossils dating back to the Wenlock epoch of the Silurian period.
The Acacus Sandstone is a geologic formation in the Ghat District, southwestern Libya. The unit preserves fossils dating back to the Llandovery epoch of the early Silurian period.
The Melbourne Formation is a geologic formation in Victoria, Australia. It preserves fossils dating back to the Ludlow epoch of the Silurian period.
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