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An authigenic origin for Precambrian greenalite: Implications for iron formation and the chemistry of ancient seawater
Persistent anoxia and the lack of a skeletal silica sink through the Precambrian would have promoted a variety of reactions between iron and dissolved silica through much of Earth’s early history.Expand
Oxygenation of the Earth's atmosphere–ocean system: A review of physical and chemical sedimentologic responses
Abstract The Great Oxidation Event (GOE) is one of the most significant changes in seawater and atmospheric chemistry in Earth history. This rise in oxygen occurred between ca. 2.4 and 2.3 Ga and setExpand
Sedimentary phosphate and associated fossil bacteria in a Paleoproterozoic tidal flat in the 1.85 Ga Michigamme Formation, Michigan, USA
Abstract Phosphorus is a nutrient fundamental to life and when it precipitates in modern environments bacteria are intimately involved in its release, concentration, and mineralization. PreservedExpand
Upper Cretaceous (Campanian) phosphorites in Jordan: implications for the formation of a south Tethyan phosphorite giant
A record of sedimentary, authigenic, and biological processes are preserved within the Upper Cretaceous (Campanian) Alhisa Phosphorite Formation (AP) in central and northern Jordan. The AP formedExpand
Paleoceanographic constraints on Precambrian phosphorite accumulation, Baraga Group, Michigan, USA
Abstract The Palaeoproterozoic Baraga Group (ca. 1850 ± 1 Ma) of northern Michigan is a ∼ 1200 m thick sedimentary succession of marine clastic, iron formation, chert, and phosphatic sedimentaryExpand
Depositional controls on Palaeoproterozoic iron formation accumulation, Gogebic Range, Lake Superior region, USA
Shallowing-upward, decametre-scale, Palaeoproterozoic iron formation cycles in northern Wisconsin record the combined effects of tectonism and changing oceanographic conditions on a storm-dominatedExpand
Coated phosphate grains: Proxy for physical, chemical, and ecological changes in seawater
Irrespective of geologic age, Phanerozoic coated phosphate grains deposited beneath productive surface waters in organic-rich paleoenvironments are of only two types. Unconformity-bounded grainsExpand
Monospecific Pliocene oyster buildups, Murray Basin, South Australia: Brackish water end member of the reef spectrum
Abstract Paleoestuarine, monospecific oyster bioherms and biostromes formed by the extant, soft-bottom oyster, Ostrea angasi , are prolific in the Pliocene Norwest Bend Formation, Murray Basin, SouthExpand
Secular changes in sedimentation systems and sequence stratigraphy
Abstract The ephemeral nature of most sedimentation processes and the fragmentary character of the sedimentary record are of first-order importance. Despite a basic uniformity of external controls onExpand
Paleoenvironmental and taphonomic controls on the occurrence of Paleoproterozoic microbial communities in the 1.88 Ga Ferriman Group, Labrador Trough, Canada
Abstract Chert and iron formation from the Ferriman Group (ca. 1.88 Ga), Labrador Trough, Canada, contain an exceptional assemblage of fossil bacteria and biofilms preserved within a well-definedExpand