Paleoecologic and Biostratigraphic Significance of Trace Fossils From Shallow- to Marginal-Marine Environments From the Middle Cambrian (Stage 5) of Jordan

Abstract

The Hanneh Member (Cambrian Stage 5) of the Burj Formation and the Umm Ishrin Formation of Jordan represent a transgressive-regressive succession that contains twenty-eight ichnotaxa, including vertical burrows (Arenicolitesisp.,Diplocraterionisp.,Gyrolithes polonicus,Rosseliaisp.,Skolithos linearis, escape trace fossils), horizontal simple burrows and trails (Archaeonassa fossulata,Gordia marina,Helminthoidichnites tenuis,Palaeophycus tubularis,Planolites beverleyensis,P. montanus), plug-shaped burrows (Bergaueria sucta), horizontal branched burrows (Asterosomaisp.,Phycodesisp.,Treptichnuscf.T. pedum), bilobate structures (various ichnospecies ofCruzianaandRusophycus), and trackways and scratch marks (Diplichnitesisp.,Dimorphichnuscf.D. obliquus,Monomorphichnusisp.). Eleven trace-fossil assemblages are identified. TheArenicolitesisp. andDiplocraterionisp. assemblages occur in transgressive tidal dunes and bars whereas theRosseliaisp. assemblage characterizes areas between tidal dunes. TheCruziana salomonisassemblage reflects a wide variety of environmental settings including channels within tidal-bar complexes, bottomsets of tidal dunes, and interdune areas. TheGordia marinaassemblage is present between dune patches. TheGyrolithes polonicusassemblage penetrates into firmground mudstone below the maximum flooding surface. TheBergaueria sucta,Archaeonassa fossulata,Rusophycus aegypticusandCruziana problematicaassemblages occur in different subenvironments of the progradational delta.Cruziana salomonisandRusophycus burjensis, originally considered indicative of an early Cambrian age, are actually middle Cambrian in their type locality. Occurrences ofCruziana jordanicaandRusophycus aegypticusprovide evidence that these ichnospecies are of the same age in Jordan and may co-exist in terms of stratigraphic distribution withC. salomonisandR. burjensis.

Ichnostratigraphy of the Ediacaran-Cambrian boundary: new insights on lower Cambrian biozonations from the Soltanieh Formation of northern Iran

“…Cruziana is best interpreted as related to combined locomotion and feeding strategy (pascichnia) (Seilacher, 2007). It is widely accepted that the main producers of Cruziana in the marine Paleozoic were trilobites or trilobitomorphs (Seilacher, 1970(Seilacher, , 1985(Seilacher, , 1992Hofmann et al, 2012). Cruziana ranges in age from early Cambrian to Holocene (Seilacher, 1970;Muñiz Guinea et al, 2015), and has been reported from a varied spectrum of paleoenvironments, ranging from typical shallow-water marine to freshwater settings (Bromley and Asgaard, 1979;Crimes, 1987).…”

Trace fossils from the Lower Muschelkalk of Raciborowice Górne (North Sudetic Synclinorium, SW Poland) and their palaeoenvironmental interpretation

“…Archaeonassa was described from lakes, deltas and shallow seas (Knaust 2007aSarkar et al 2009;Hofmann et al 2012;Mángano et al 2013).…”

“…It is common in the Upper Buntsandstein (Röt), Lower Muschelkalk (Knaust 2007a) Skolithos is a dwelling burrow (domichnion) of suspension-feeding annelids (polychaete), sipunculans, phoronids, crustaceans (Alpert 1974;Miller and Knox 1985;Gouramanis et al 2003;Bressan and Palma 2009;Desjardins et al 2010;Hofmann et al 2012;Knaust 2012;Baucon and Felletti 2013a). It is interpreted as fodinichnia or equilibrichnia of deposit feeders (Kim et al 2002, Davies et al 2009Loughlin and Hillier 2010).…”

On the ichnofossil Treptichnus pedum: inferences from the Nagaur Sandstone, Marwar Supergroup, India

“…The ichnogenera Rusophycus, Diplichnites and Cruziana are also found preserved on the same surface however, no short range taxon is found in the assemblage (Fig. 9E) suggesting that the zones of T. pedum cross over in these strata and occur together with Rusophycus throughout the Cambrian (Jensen & Mens 2001, Hofmann et al 2012, Srivastava 2012a, Pandey et al 2014. The Agronomic Revolution (Seilacher & Pflüger 1994, Seilacher 1999 subsequently triggered another revolution in selection of the substrate changes by the benthic organisms (Mángano & Buatois 2017).…”