Lithology and origin of Middle Ordovician calcareous mudmound at Meiklejohn Peak, southern Nevada

An exhumed Palaeozoic underwater scenery: the Visean mud mounds of the eastern Anti-Atlas (Morocco)

“…Although they consist mainly of fine-grained carbonate they have, however, represented a habitat for a large variety of sessile organisms. Impressive examples of mud mounds have been described from Ordovician (Ross et al, 1975;Vennin et al, 1998), Silurian (Bourque and Gignac, 1983;De Freitas and Dixon, 1995) and Devonian settings (Brachert et al, 1992;Wendt et al, 1997;Kaufmann, 1998), but this type of buildup is most widespread in the Early Carboniferous, in particular, in the Waulsortian facies of England, Ireland and Belgium (Bolton et al, 1982;Lees, 1988;Bridges et al, 1995). The name is derived from the village of Waulsort in the Dinant Syncline of southern Belgium and has subsequently been applied to similar constructions in other parts of the world, including the United States and Canada.…”

The Triassic Chitistone Limestone, Wrangell Mountains, Alaska: stressing detailed descriptions of sabkha facies and other rocks in lower parts of the Chitistone and their relations to Kennecott-type copper deposits

“…Bathurst (1959) (Lees, 1961, p. 103, fig. 2; Lees, 1964;Schwarzacher, 1961Schwarzacher, , p. 1483Ross et al, 1975). Most of the Stromatactis described are on We interpret the zebra beds as having been deposited in a sabkha environment.…”

Ordovician Meiklejohn carbonate mound, Nevada

“…308-11) Dr Robin Bathurst published a useful discussion on the origin and sedimentological significance of stromatactis and of 'zebra rock' in connection with a critical review of a paper on the Ordovician Meiklejohn carbonate mound in Nevada (Ross, Jaanusson & Friedman, 1975). Much of Bathurst's discussion is centred around the origin of the spar in the 'zebra rock' which was treated in the publication by R. J. Ross, Jr.…”

“…There exist numerous examples showing that subsequently the radiaxial crystals or their precursors (at this stage it is mostly difficult to keep these generations apart) began to replace skeletal grains which formed the original base surfaces. An example is shown in Ross et al (1975, fig. 29) where a portion of an echinoderm grain is in part replaced by crystals of radiaxial calcite.…”