摘要:

Recent discoveries of abundant fossil footprints from the new Grand Staircase‐Escalante National Monument of southern Utah, have important implications for the spatial and temporal distribution of Mesozoic vertebrates in Triassic and Jurassic time. Since the monument's creation in 1996, fossil footprints have been reported from at least seven formations in the Mesozoic (Triassic‐Cretaceous) within the monument. By far the most significant of these discoveries are sauropod and theropod tracks from the upper part of the Middle Jurassic Entrada Sandstone and a largeApatopustrackway from the Late Triassic Chinle Formation. Tracks in the Entrada Sandstone are found at the same stratigraphic level as those in the Moab megatracksite, and so considerably extend this large ichnological complex. A wide‐gauge sauropod trackway (cf.Brontopodus)from this unit represents the first reported from the Entrada Sandstone, and so is the oldest known from the western United States. This trackway also reveals a tail trace, which is the first reliable record of a sauropod tail trace.

ISSN:1042-0940    

DOI:10.1080/10420940009380158

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

An occurrence of"Glossifungites saxicava”;Lomnicki(=Rhizocorallium jenenseZenker) is redescribed from its type area in Lviv, Ukraine, after more than 100 years since its first report. This trace fossil densely penetrates a Miocene transgressive surface cut in Cretaceous marlstones. Its occurrence is restricted to the top layer of the marlstones, where it was formed in a firmground typical of theGlossifungitesichnofacies. Most probably, the trace fossil was produced during a period of non‐deposition shortly before and at the beginning of deposition of Miocene strata by opportunistic suspension‐feeding organisms, possibly crustaceans.

ISSN:1042-0940    

DOI:10.1080/10420940009380159

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Three new ichnotaxa are described from Cenozoic paralic to continental sediments on the west coast of South Africa.Stellavelum arborensisandStellavelum uncinumare assigned to a mixedSkolithosandCruzianaichnofacies andTermitichnus namibiensisis assigned to theTermitichnusichnofacies. An interpretation of the sedimentary record shows that theStellavelumtrace makers were probably sediment ingesting annelids that lived in dense colonies in sheltered lagoonal environments during Neogene times. TheTermitichnus namibiensistrace fossils are interpreted as actively backfilled termite nests which form an early to mid‐Pleistocene palimpsest, terrestrial ichnofabric which is superimposed on the older marine sediments.

ISSN:1042-0940    

DOI:10.1080/10420940009380160

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

The ichnospeciesBueckeburgichnus maximus(Kuhn 1958) is amended and illustrated on the basis of type and topotype material, from the Lower Cretaceous of Germany, showing that previous illustrations were morphologically incorrect and misleading. The track is unequivocally that of a large functionally tridactyl theropod, but can not confidently be attributed to a megalosaurid dinosaur, as suggested by ichnological tradition.Bueckeburgichnushas been compared with theropod tracks from the Upper Jurassic of Portugal labeled asEutynichnium, Megalosaurus, MegalosauripusandMegalosauropus,but the comparisons are tenuous and compromised by invalid ichnotaxonomic treatment of all four ichnogenera.Megalosaurusmust be abandoned as an ichnotaxonomic descriptor. The status ofMegalosauripus, MegalosauropusandEutynichniumis under further investigation but preliminary results suggest thatBueckeburgichnus maximusis distinct from any ichnospecies assigned to these two ichnogenera.

ISSN:1042-0940    

DOI:10.1080/10420940009380161

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Exposures of the Tuscaloosa Formation in eastern Alabama (U.S.A.) provided an opportunity to examine ichnofossils and ichnofabrics within Cretaceous fluvial facies. Floodplain mudstones are completely bioturbated and dominated by backfilled burrows most allied withTaenidium serpentinum.These burrows likely reflect the work of insects or oligochaetes that occupied soft, moist proximal floodplain substrates. Although the affinities and ethology of the tracemakers and the precise environmental conditions that prevailed during burrowing cannot be confidently inferred,Tnenidium‐dominated ichnofabrics of the mudstones can be assigned to theScoyeniaichnofacies in the narrower sense of several recent authors (e.g., Buatois and Mángano, 1985).

ISSN:1042-0940    

DOI:10.1080/10420940009380162

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

ISSN:1042-0940    

DOI:10.1080/10420940009380157

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor