The Khok Kruat Formation is the upper part of the Khorat Group,which consists of upper Lower Cretaceous non-marine sedimentary rocks in northeastern Thailand.Many dinosaur footprints have been known from the upper Low...The Khok Kruat Formation is the upper part of the Khorat Group,which consists of upper Lower Cretaceous non-marine sedimentary rocks in northeastern Thailand.Many dinosaur footprints have been known from the upper Lower Cretaceous(Aptian-Albian)Khok Kruat Formation at the Huai Dam Chum(Tha Uthen)site,northeastern Thailand.Approximately 600 tracks occur in thin mudstone layer of the northern part of the outcrop at the Huai Dam Chum track site.Two types of footprints,small-sized theropod and crocodylomorph are imprinted with mud cracks and ripple marks on the thin mud layer.Most of footprints are referred to cf.Asianopodus,and are imprinted by small-sized theropoda,probably ornithomimosauria.Theropod tracks are mainly separated into two groups,Group A and Group B.From ichnological viewpoints,the small-sized theropod track assemblage indicates the herd behaviour and its idiosyncratic group composition.In particular,the histogram of size-frequency measurements of Group A shows the anomalous bimodal distribution.We consider that there are two hypotheses;the first one is due to the male-female difference,and the second is a result of the different growing stage.展开更多
In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well....In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well. Actually, the dinosaur footprints were found by local inhabitants much earlier in history, but not for science. The slabs bearing the dinosaur footprints were collected for domestic use, such as building stones, millstones, cellar covers, sheepfold fences, windlass holders, etc. This paper is to describe the dinosaur footprints on both sides of three slabs used for cellar covers, sheepfold fences and windlass holders by the local people. 24 dinosaur footprints and 4 trackways have been recognized and all of them belong to theropod. Four kinds of dinosaur footprints are identified, including 1 new ichnogenus and 2 new ichnospecies： （1） Shanbeipus caudatus ichnogen, et ichnosp, nov.; （2） Pengxianpus yulinensis ichnosp, nov.; （3） Eubrontes ichnosp; （4） Kayentapus ichnosp. Dinosaur-footprint-bearing beds were initially identified as the Fuxian Formation of the Lower Jurassic. Multipal dinosaur footprints associated with fragment plant fossils suggest a humid fluviolacustrine environment setting in the Ordos Basin during the early period of the Jurassic.展开更多
A new dinosaur tracksite was discovered in a steeply inclined sandstone layer of the Middle Jurassic Sanjianfang Formation in the Shanshan area of the Turpan Basin. The site is the first record of dinosaur footprints ...A new dinosaur tracksite was discovered in a steeply inclined sandstone layer of the Middle Jurassic Sanjianfang Formation in the Shanshan area of the Turpan Basin. The site is the first record of dinosaur footprints from Xinjiang Province in northwestern China. More than 150 tridactyl theropod dinosaur footprints are preserved as positive hyporeliefs on the lower bedding plane of a fine-grained sandstone body. Most of the footprints are isolated and appear to be randomly distributed. Some show well defined phalangeal pads, heels and rarely indistinct impressions of the distal part of the metatarsus. Two distinct morphotypes are present: a larger type with relatively broad pads shows similarities to Changpeipus and Megalosauripus, and a slightly smaller, slender and gracile type which is similar to Grallator, Eubrontes and Anchisauripus. In both morphotypes, digit III is the longest with a length between 11.4 and 33.6 cm. A single imprint shows prominent scratches, probably formed during slipping of the track maker.展开更多
文摘The Khok Kruat Formation is the upper part of the Khorat Group,which consists of upper Lower Cretaceous non-marine sedimentary rocks in northeastern Thailand.Many dinosaur footprints have been known from the upper Lower Cretaceous(Aptian-Albian)Khok Kruat Formation at the Huai Dam Chum(Tha Uthen)site,northeastern Thailand.Approximately 600 tracks occur in thin mudstone layer of the northern part of the outcrop at the Huai Dam Chum track site.Two types of footprints,small-sized theropod and crocodylomorph are imprinted with mud cracks and ripple marks on the thin mud layer.Most of footprints are referred to cf.Asianopodus,and are imprinted by small-sized theropoda,probably ornithomimosauria.Theropod tracks are mainly separated into two groups,Group A and Group B.From ichnological viewpoints,the small-sized theropod track assemblage indicates the herd behaviour and its idiosyncratic group composition.In particular,the histogram of size-frequency measurements of Group A shows the anomalous bimodal distribution.We consider that there are two hypotheses;the first one is due to the male-female difference,and the second is a result of the different growing stage.
基金the BJAST Youth Backbone Training Plan(No.2014-08) for the financial support
文摘In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well. Actually, the dinosaur footprints were found by local inhabitants much earlier in history, but not for science. The slabs bearing the dinosaur footprints were collected for domestic use, such as building stones, millstones, cellar covers, sheepfold fences, windlass holders, etc. This paper is to describe the dinosaur footprints on both sides of three slabs used for cellar covers, sheepfold fences and windlass holders by the local people. 24 dinosaur footprints and 4 trackways have been recognized and all of them belong to theropod. Four kinds of dinosaur footprints are identified, including 1 new ichnogenus and 2 new ichnospecies： （1） Shanbeipus caudatus ichnogen, et ichnosp, nov.; （2） Pengxianpus yulinensis ichnosp, nov.; （3） Eubrontes ichnosp; （4） Kayentapus ichnosp. Dinosaur-footprint-bearing beds were initially identified as the Fuxian Formation of the Lower Jurassic. Multipal dinosaur footprints associated with fragment plant fossils suggest a humid fluviolacustrine environment setting in the Ordos Basin during the early period of the Jurassic.
文摘A new dinosaur tracksite was discovered in a steeply inclined sandstone layer of the Middle Jurassic Sanjianfang Formation in the Shanshan area of the Turpan Basin. The site is the first record of dinosaur footprints from Xinjiang Province in northwestern China. More than 150 tridactyl theropod dinosaur footprints are preserved as positive hyporeliefs on the lower bedding plane of a fine-grained sandstone body. Most of the footprints are isolated and appear to be randomly distributed. Some show well defined phalangeal pads, heels and rarely indistinct impressions of the distal part of the metatarsus. Two distinct morphotypes are present: a larger type with relatively broad pads shows similarities to Changpeipus and Megalosauripus, and a slightly smaller, slender and gracile type which is similar to Grallator, Eubrontes and Anchisauripus. In both morphotypes, digit III is the longest with a length between 11.4 and 33.6 cm. A single imprint shows prominent scratches, probably formed during slipping of the track maker.
