The Lower Cretaceous mixed siliciclastic-carbonate successions of the Boulouha Formation at the type locality in the Dahar escarpment of southern Tunisia have yielded a new discovered assemblage of bivalves which cont...The Lower Cretaceous mixed siliciclastic-carbonate successions of the Boulouha Formation at the type locality in the Dahar escarpment of southern Tunisia have yielded a new discovered assemblage of bivalves which contains Anomia laevigata (Sowerby);Modiolus sp. cf. M. dahuashuensis (Yu et Li);Astarte sp.;and ?Mytilus sp.. The temporal distribution of the Anomia laevigata (Sowerby) and Modiolus sp. cf. M. dahuashuensis (Yu et Li) is limited to the Aptian formations of northeastern China, Japan and Korea, thus we suggest a Hauterivian-Barremian age for the Boulouha Formation. Henceforth, the new biostratigraphic data are used to improve a regional chronostratigraphic correlation between the lower Cretaceous strata of the Saharan Platform domain and those coeval from the Chotts domain.展开更多
Following votes by the Barremian Working Group,the International Subcommission on Cretaceous Stratigraphy and the International Commission on Stratigraphy,the Executive Committee of the International Union of Geologic...Following votes by the Barremian Working Group,the International Subcommission on Cretaceous Stratigraphy and the International Commission on Stratigraphy,the Executive Committee of the International Union of Geological Sciences unanimously approved in March 2023 the Global Stratotype Section and Point(GSSP)for the Barremian Stage(Lower Cretaceous).The base of the Barremian Stage is defined at the base of bed 171 of the Río Argos section,near Caravaca(SE Spain)and correlated by the first appearance of the ammonite species Taveraidiscus hugii.This event falls within the NC5C calcareous nannofossil Subzone,the Lilliputianella semielongata planktonic foraminiferal Zone,and the Dorothia ouachensis benthic foraminiferal Zone.It roughly coincides with the beginning of a slightly negative trend interval in theδ^(13)C curve.Indirect calibration to the magnetostratigraphic scale suggests that the boundary falls in the lowermost part of polarity chron M3r.According to the astrochronological analysis,a time interval of 0.74 myr separates the beginning of the late Hauterivian Faraoni Episode from the base of the Barremian,which is dated at 125.77 MA.展开更多
Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are （in ascending order）： the lmpardecispora-Aequitriradites- ...Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are （in ascending order）： the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data.展开更多
The abundant fossils of early angiosperms found in the Yixian Formation （125 Ma, Early Cretaceous） have demonstrated unexpectedly high diversity and various reproductive strategies, and thus have shed new light on e...The abundant fossils of early angiosperms found in the Yixian Formation （125 Ma, Early Cretaceous） have demonstrated unexpectedly high diversity and various reproductive strategies, and thus have shed new light on early angiosperm evolution. Here, using light microscope and scanning electron microscope, we document several fructifications of Baicarpus gen. nov. from Liaoning province, China. Each fructification of the new taxon includes several apocarpous carpels/fruits attached in an urn-formed gynobase. Each fruit/carpel has a persistent straight style and an ovary enclosing a single seed. These fossil plants demonstrate a new floral organization and thus enhance our understanding of the diversity of angiosperms in the Yixian Formation. Together with previously reported ones, this fossil angiosperm suggests an origin time for angiosperms earlier than widely accepted.展开更多
This palaeontological study focuses on the sedimentology and palaeofauna of Areia do Mastro locale in Cabo Espichel (Sesimbra, south of Lisbon). Two main geological formations are identified in Areia do Mastro: the Ar...This palaeontological study focuses on the sedimentology and palaeofauna of Areia do Mastro locale in Cabo Espichel (Sesimbra, south of Lisbon). Two main geological formations are identified in Areia do Mastro: the Areia do Mastro Formation and the Papo-Seco Formation. We report herein the fossilized vertebrate and invertebrate remains from the basal deposits (marls, sands and gravels) of Papo-Seco Formation assigned to Lower Barremian (Lower Cretaceous). The sedimentological analysis and identified palaeofauna indicated a changing environment with important biological and ecological aspects. Extensive periods of sea level fluctuations and subsequent transgressive marine episodes had as a result the continental infralittoral internal platform to be gradually replaced by a lagoon, as revealed from the fossil remains embodied in the sediments during the formation of the afore mentioned sedimentary sequences.展开更多
New well-preserved rudist materials come from the Barremian–Turonian marine formations in the Yelleg, Minsherah, Maaza, and Raghawi sections in North Sinai, northern Egypt. There, 17 discovered rudist species belongi...New well-preserved rudist materials come from the Barremian–Turonian marine formations in the Yelleg, Minsherah, Maaza, and Raghawi sections in North Sinai, northern Egypt. There, 17 discovered rudist species belonging to 13 genera and seven taxonomic families are described in detail as follows: Eoradiolites plicatus(Conrad), Eoradiolites liratus(Conrad), Praeradiolites ponsianus(d'Archiac), Archaeoradiolites sp., Bournonia africana Douvillé, Bournonia fourtaui Douville, Biradiolites lombricalis(d'Orbigny), Biradiolites zumoffeni Douville, Radiolites lewyi lewyi Parnes, Radiolites sauvagesi(d'Hombres-Firmas), Durania arnaudi(Choffat), Toucasia carinata(Matheron), Toucasia sp., Neocaprina raghawiensis Steuber and Bachmann, Sellaea sp., Ichthyosarcolites sp. and Horoiopleura sp.. The Cenomanian deposits in the northern Eastern desert of Egypt only contain E. liratus. The domination of the Cenomanian rudist species in North Sinai, however, is attributed to changes in the platform, which passes mainly from carbonate in the north to siliciclastics in the south. The presence of Horiopleura sp. in the late Barremian-early Aptian deposits is documented for the first time, which suggests the expansion of taxa of the genus Horiopleura Douville to North Sinai during this interval. The age of the rudist species is documented from the late Barremian-Turonian formations, with their geographic distribution in the Mediterranean region considered..展开更多
Spatangoid echinoids belonging to Heteraster found in the Lower Cretaceous limestones and calcareous deposits of the Tirgan and Sarcheshmeh formations(Barremian-Aptian)in the Bahman jan-Bala stratigraphic section on t...Spatangoid echinoids belonging to Heteraster found in the Lower Cretaceous limestones and calcareous deposits of the Tirgan and Sarcheshmeh formations(Barremian-Aptian)in the Bahman jan-Bala stratigraphic section on the northern flank of the Borouj syncline,situated in the eastern Kopet-Dagh Basin,northeastern Iran are assessed as a sexually dimorphic species.Sexual dimorphism is a common feature in echinoids and,in this study of Heteraster renngarteni Poretzkaja,1961,sexual dimorphism has been detected for the first time in the family Toxasteridae.展开更多
Due to the water demand growth in southwestern Tunisia, particularly in Segui Gafsa-Tozeur area, the Tunisian Government launched a research program for new water resources in the lower Cretaceous layers within the Ha...Due to the water demand growth in southwestern Tunisia, particularly in Segui Gafsa-Tozeur area, the Tunisian Government launched a research program for new water resources in the lower Cretaceous layers within the Hauterivian and Barremian age. The present study highlights the major results of this project and defines the ability of the Barremian and Hauterivian series to be or not as good usable aquifers in this region. Seismic data show that the studied levels are located in deep trough with a very high depth. The water collected from the drilled wells in this region shows a very high salinity (80 g/l to 130 g/l) with a very low water level (끪 m/TN). These water levels are in hydrological isolation by faulting (faults trending NE-SW and NW-SE) with the Jerid area, where these layers are good water bearing. Thus, the studied series can't be considered as encouraging usable aquifers in the future. These results are crucial to make a decision and represent the guideline for research strategies in South-West Tunisia. Consequently, the government focuses on water search within the Turonian level which showed much more encouraging signs.展开更多
The history of amber and its trade in Lebanon dates back to ancient times,during the Phoenician civilization.Amber in Lebanon can be found in over 450 outcrops,comprising approximately 10%of the country’s land.Some o...The history of amber and its trade in Lebanon dates back to ancient times,during the Phoenician civilization.Amber in Lebanon can be found in over 450 outcrops,comprising approximately 10%of the country’s land.Some of these outcrops are Late Jurassic(Kimmeridgian)in age,while the majority are Early Cretaceous(early Barremian).The Early Cretaceous amber found in Lebanon is the oldest amber with extensive biological inclusions,making it a crucial source of knowledge regarding continental palaeobiodiversity during the Early Cretaceous period.This period is widely recognized as witnessing the first occurrence and early evolution of angiosperms,representing a critical time for the co-evolution between flowering plants and insects.In Lebanese amber,biological inclusions often serve as records of the earliest representatives of modern living insect families or the youngest ones for extinct families.展开更多
文摘The Lower Cretaceous mixed siliciclastic-carbonate successions of the Boulouha Formation at the type locality in the Dahar escarpment of southern Tunisia have yielded a new discovered assemblage of bivalves which contains Anomia laevigata (Sowerby);Modiolus sp. cf. M. dahuashuensis (Yu et Li);Astarte sp.;and ?Mytilus sp.. The temporal distribution of the Anomia laevigata (Sowerby) and Modiolus sp. cf. M. dahuashuensis (Yu et Li) is limited to the Aptian formations of northeastern China, Japan and Korea, thus we suggest a Hauterivian-Barremian age for the Boulouha Formation. Henceforth, the new biostratigraphic data are used to improve a regional chronostratigraphic correlation between the lower Cretaceous strata of the Saharan Platform domain and those coeval from the Chotts domain.
文摘Following votes by the Barremian Working Group,the International Subcommission on Cretaceous Stratigraphy and the International Commission on Stratigraphy,the Executive Committee of the International Union of Geological Sciences unanimously approved in March 2023 the Global Stratotype Section and Point(GSSP)for the Barremian Stage(Lower Cretaceous).The base of the Barremian Stage is defined at the base of bed 171 of the Río Argos section,near Caravaca(SE Spain)and correlated by the first appearance of the ammonite species Taveraidiscus hugii.This event falls within the NC5C calcareous nannofossil Subzone,the Lilliputianella semielongata planktonic foraminiferal Zone,and the Dorothia ouachensis benthic foraminiferal Zone.It roughly coincides with the beginning of a slightly negative trend interval in theδ^(13)C curve.Indirect calibration to the magnetostratigraphic scale suggests that the boundary falls in the lowermost part of polarity chron M3r.According to the astrochronological analysis,a time interval of 0.74 myr separates the beginning of the late Hauterivian Faraoni Episode from the base of the Barremian,which is dated at 125.77 MA.
基金This research is financialy supported by the National Natural Science Foundation of China(No.49894190)the Scientific Key Foundation of Daqing Oilfield Company Ltd.(No.QR/A04-2-01).
文摘Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are （in ascending order）： the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data.
基金supported by the National Basic Research Program of China(973 Program 2012CB821901)the Knowledge Innovation Program of the Chinese Academy of Sciences(Porgram KZCX2-YW-154)
文摘The abundant fossils of early angiosperms found in the Yixian Formation （125 Ma, Early Cretaceous） have demonstrated unexpectedly high diversity and various reproductive strategies, and thus have shed new light on early angiosperm evolution. Here, using light microscope and scanning electron microscope, we document several fructifications of Baicarpus gen. nov. from Liaoning province, China. Each fructification of the new taxon includes several apocarpous carpels/fruits attached in an urn-formed gynobase. Each fruit/carpel has a persistent straight style and an ovary enclosing a single seed. These fossil plants demonstrate a new floral organization and thus enhance our understanding of the diversity of angiosperms in the Yixian Formation. Together with previously reported ones, this fossil angiosperm suggests an origin time for angiosperms earlier than widely accepted.
基金Authors thank Centro Português de Geo-História e Pré-História,for supporting the field and laboratory work,and all the team members who have collaborated in the fieldwork.
文摘This palaeontological study focuses on the sedimentology and palaeofauna of Areia do Mastro locale in Cabo Espichel (Sesimbra, south of Lisbon). Two main geological formations are identified in Areia do Mastro: the Areia do Mastro Formation and the Papo-Seco Formation. We report herein the fossilized vertebrate and invertebrate remains from the basal deposits (marls, sands and gravels) of Papo-Seco Formation assigned to Lower Barremian (Lower Cretaceous). The sedimentological analysis and identified palaeofauna indicated a changing environment with important biological and ecological aspects. Extensive periods of sea level fluctuations and subsequent transgressive marine episodes had as a result the continental infralittoral internal platform to be gradually replaced by a lagoon, as revealed from the fossil remains embodied in the sediments during the formation of the afore mentioned sedimentary sequences.
基金King Saud University for funding this work through the Researchers Supporting Project(no.RSP-2020/149)。
文摘New well-preserved rudist materials come from the Barremian–Turonian marine formations in the Yelleg, Minsherah, Maaza, and Raghawi sections in North Sinai, northern Egypt. There, 17 discovered rudist species belonging to 13 genera and seven taxonomic families are described in detail as follows: Eoradiolites plicatus(Conrad), Eoradiolites liratus(Conrad), Praeradiolites ponsianus(d'Archiac), Archaeoradiolites sp., Bournonia africana Douvillé, Bournonia fourtaui Douville, Biradiolites lombricalis(d'Orbigny), Biradiolites zumoffeni Douville, Radiolites lewyi lewyi Parnes, Radiolites sauvagesi(d'Hombres-Firmas), Durania arnaudi(Choffat), Toucasia carinata(Matheron), Toucasia sp., Neocaprina raghawiensis Steuber and Bachmann, Sellaea sp., Ichthyosarcolites sp. and Horoiopleura sp.. The Cenomanian deposits in the northern Eastern desert of Egypt only contain E. liratus. The domination of the Cenomanian rudist species in North Sinai, however, is attributed to changes in the platform, which passes mainly from carbonate in the north to siliciclastics in the south. The presence of Horiopleura sp. in the late Barremian-early Aptian deposits is documented for the first time, which suggests the expansion of taxa of the genus Horiopleura Douville to North Sinai during this interval. The age of the rudist species is documented from the late Barremian-Turonian formations, with their geographic distribution in the Mediterranean region considered..
基金The authors appreciate the hard work and help of our friends in the Geological Survey of Iran,North East Territory(GSINET),especially Dr.Jafar Taheri.The authors are especially grateful for the linguistic helps and efforts of Susan Turner(Brisbane).
文摘Spatangoid echinoids belonging to Heteraster found in the Lower Cretaceous limestones and calcareous deposits of the Tirgan and Sarcheshmeh formations(Barremian-Aptian)in the Bahman jan-Bala stratigraphic section on the northern flank of the Borouj syncline,situated in the eastern Kopet-Dagh Basin,northeastern Iran are assessed as a sexually dimorphic species.Sexual dimorphism is a common feature in echinoids and,in this study of Heteraster renngarteni Poretzkaja,1961,sexual dimorphism has been detected for the first time in the family Toxasteridae.
文摘Due to the water demand growth in southwestern Tunisia, particularly in Segui Gafsa-Tozeur area, the Tunisian Government launched a research program for new water resources in the lower Cretaceous layers within the Hauterivian and Barremian age. The present study highlights the major results of this project and defines the ability of the Barremian and Hauterivian series to be or not as good usable aquifers in this region. Seismic data show that the studied levels are located in deep trough with a very high depth. The water collected from the drilled wells in this region shows a very high salinity (80 g/l to 130 g/l) with a very low water level (끪 m/TN). These water levels are in hydrological isolation by faulting (faults trending NE-SW and NW-SE) with the Jerid area, where these layers are good water bearing. Thus, the studied series can't be considered as encouraging usable aquifers in the future. These results are crucial to make a decision and represent the guideline for research strategies in South-West Tunisia. Consequently, the government focuses on water search within the Turonian level which showed much more encouraging signs.
文摘The history of amber and its trade in Lebanon dates back to ancient times,during the Phoenician civilization.Amber in Lebanon can be found in over 450 outcrops,comprising approximately 10%of the country’s land.Some of these outcrops are Late Jurassic(Kimmeridgian)in age,while the majority are Early Cretaceous(early Barremian).The Early Cretaceous amber found in Lebanon is the oldest amber with extensive biological inclusions,making it a crucial source of knowledge regarding continental palaeobiodiversity during the Early Cretaceous period.This period is widely recognized as witnessing the first occurrence and early evolution of angiosperms,representing a critical time for the co-evolution between flowering plants and insects.In Lebanese amber,biological inclusions often serve as records of the earliest representatives of modern living insect families or the youngest ones for extinct families.
