摘要:

Shell beds containing characteristic trace fossils of the Early Pleistocene Seogwipo Formation represent a storm‐influenced succession. They generally consist of: (1) initial firmground substrates in foreshore to offshore environments as indicated by theGlossifungitesichnofacies, includingGastrochaenolitesandThalassi‐noides, (2) basal storm‐erosive lag deposits, (3) reworked shell beds of main storm deposits, (4) massive sandstone of waning storm deposits containingSkolithos, and (5) bioturbated sandstones of post‐storm offshore deposits indicated by theCruzianaichnofacies that includeChondrites, Helminthopsis, Laminites, Phy‐codesandThalassinoides.This succession of shell beds reflects a gradational decrease in hydraulic energy levels induced by storms. Trace fossils includingGastrochaenolites lapidicus, Helminthopsisichnosp.,Laminitesichnosp.Thalassinoidescf.paradoxicaandT.cf.suevicusare systematically described from shell beds of the Seogwipo Formation.

ISSN:1042-0940    

DOI:10.1080/10420949709386408

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Values of hindlimb height and glenoacetabular length are estimated in two ways: a) from an Aptian age sauropod trackway 13 meters long at a site (El Sobaquillo) in La Rioja Province (Spain), and b) from published skeletal reconstructions in Norman (1985), McIntosh (1990) and Farlow (1992). Results that best fit the presently available data are obtained using formulae suggested by Ishigaki (1988) and Lockley et al. (1986) for hindlimb height, and that employed by Far‐low et al. (1989) for glenoacetabular length. Our estimate of the glenoacetabular lengths of trackmakers from El Sobaquillo is consistent with a hypothesis that the sauropods were moving by amble walking. This interpretation is supported by data from other trackways found in La Rioja.

ISSN:1042-0940    

DOI:10.1080/10420949709386409

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Dinosaur footprints occur in shallow marine sedimentary units of the Berriasian Villar del Arzobispo Formation in the Aliaga basin, NE Spain. Las Cerradicas is a small outcrop (25 m2), near Galve, with four dinosaur trackways. Three tridactyl trackways indicate bipedal animals, and have parallel orientation. A fourth or‐nithopod trackway indicates a quadrupedal animal and is the smallest among any reported in the literature (L = 23 cm, W = 23 cm of pes tracks). It has manus prints that are oval‐shaped impressions. These and other recent discoveries shed much light on the abundance of quadrupedal ornithopods during the early Cretaceous.

ISSN:1042-0940    

DOI:10.1080/10420949709386410

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

A tetradactyl pes impression and tridactyl manus impression are described as the type specimen ofHatcherichnus sanjuanensisichnogen. et ichnosp. nov., a probable large crocodilian ichnite from the Salt Wash Member of the Upper Jurassic Morrison Formation in eastern Utah. A similar pes track from the Morrison Formation at Garden Park, Colorado, may also belong to this ichnogenus. The type specimen from Utah consists of plaster replicas of natural casts of a left pes impression and a left manus impression. Associated with the type specimen were possible tail and body drag impressions. The tracks do not appear to be part of a walking trackway and may be swim tracks associated with an animal in shallow water. The tracks occur at a visible contact between slightly fining‐upward channel sandstone units.

ISSN:1042-0940    

DOI:10.1080/10420949709386411

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Diplocraterion luniformeoccurs abundantly in the Cretaceous Hasandong Formation of the Jinju area, Korea. The Hasandong Formation consists of fluvial deposits mainly composed of sandstone, siltstone, mudstone and shale. The formation contains freshwater bivalves such asTrigonioidessp. andPlicatouniosp., fossil tree stumps, carbonized wood, stromatolites, caliche nodules, current ripples and desiccation cracks. The trace fossilsPlanolitesichnosp.,Skolithosichnosp. andTaenid‐iumichnosp. are also commonly observed.Diplocraterion luniformeoccurs in the gray shale which is considered to have been deposited in floodplain lake environments. This report represents an unusual record of a nonmarine occurrence ofDiplocraterion, which has previously been generally regarded as a diagnostic marine trace fossil.

ISSN:1042-0940    

DOI:10.1080/10420949709386412

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Ganei (Switzerland) is a classical locality for trace fossils. At this site, Heer (1877) described a large number of trace fossils, several of which were new taxa. The trace fossils occur in thin‐bedded turbidites in which the basal divisions of the Bouma sequence are typically absent; the turbidites are assigned to the Ganei Slates and are Eocene in age. They are interpreted to have been deposited in an overbank environment within an upper to middle fan area distal to a channel. Two trace‐fossil associations occur: the first (I) is characterized by bulldozing organisms producing biodeformational structures,Scolica, andNereites irregularis;the second (II) association shows a distinct tiering pattern with near‐surface graphoglyptids and a mixed layer with simple tubes such as cf.PalaeophycusandPlanolites, plus patterned tubes such asNereites cirrinalis, andChondrites.Deeper turbidite layers were colonized byChondritesandGyro‐phyllites.All trace fossils show a normal size spectrum compared to previously studied trace‐fossil associations, so the degree of oxygenation probably did not influence the composition of either trace‐fossil association. Seafloor sediment was probably soft and did not affect the trace‐fossil associations. Sedimentation rate and event frequency did not change and are estimated to have been in a range of 5–10 cm/1000 years and 2–5 events per 1000 years, respectively. The composition of trace‐fossil associations I and II is therefore interpreted to have been controlled by the benthic food content being higher for trace‐fossil association I than for II.

ISSN:1042-0940    

DOI:10.1080/10420949709386413

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

There have been many research attempts to infer the track‐maker from a fossil footprint. However, it does not seem that prediction of the footprint from a mounted skeleton has yet been attempted. The body form of the desmostylian is hypothesized to have a peculiar lateral‐type limb posture. If fossil desmostylian footprints were to be found, this hypothesis on reconstruction of the desmostylian skeleton could be tested. In order to stimulate such a discovery, the presumed footprint and trackway ofDesmostylusare postulated here. The footprint and trackway are inferred from skeletons and comparisons with some living mammals. They are characterized by a short, wide footprint with four divergent toes and pad, short stride and wide trackway.

ISSN:1042-0940    

DOI:10.1080/10420949709386414

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

ISSN:1042-0940    

DOI:10.1080/10420949709386407

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor