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The Late Tremadocian(Ordovician)Graptolite Kiaerograptus from Central Hunan,China:Taxonomy and Biostratigraphy 被引量:2
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作者 LI Ming LI Lixia WANG Wenhui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期1-12,共12页
Well-preserved graptolites of the genus Kiaerograptus are first reported from the upper Tremadocian Yinchupu Formation in the Nanba section,Yiyang,Hunan Province,South China,including four species,i.e.,Kiaerograptus l... Well-preserved graptolites of the genus Kiaerograptus are first reported from the upper Tremadocian Yinchupu Formation in the Nanba section,Yiyang,Hunan Province,South China,including four species,i.e.,Kiaerograptus lauzonensis(Erdtmann,1966),Kiaerograptus stoermeri(Erdtmann,1965),Kiaerograptus cf.supremus?Lindholm,1991,and Kiaerograptus sp.,which are robust in form.Based on these new specimens,the Kiaerograptus biozone is established for the first time in South China,increasing the late Tremadoc graptolite biozones in South China from four to five,in ascending order as follows:the Adelograptus tenellus biozone,the Aorograptus victoriae biozone,the Kiaerograptus biozone,the Sagenograptus murrayi biozone,and the Hunnegraptus copiosus biozone.A review of the occurrence records for robust Kiaerograptus species worldwide reveals that the distribution is restricted to the Aorograptus victoriae biozone and Kiaerograptus biozone in the late Tremadocian.This limited stratigraphical distribution makes Kiaerograptus a valuable taxon for precise biostratigraphical correlation at both the regional and global scales. 展开更多
关键词 PALEONTOLOGY biostratigraphy GRAPTOLITES anisograptid TREMADOCIAN Hunan Province
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Biostratigraphy, Palynofacies and Organic Geochemical Characterization of Three Wells, Western Offshore Niger Delta Nigeria
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作者 Oluwafemi Gabriel Ogunsanya Joshua Babatunde Asere +2 位作者 Olugbenga Ademola Boboye Kehinde Sunday Bosikun Grace Adewumi Adegboye 《Open Journal of Geology》 CAS 2023年第5期504-535,共32页
Ditch samples from AP-4, ER-51 and UK-2 offshore Niger Delta were subjected to biostratigraphic and organic geochemical analyses which entail foraminiferal, palynological, Spore Colour Index (SCI), Rock-Eval Pyrolysis... Ditch samples from AP-4, ER-51 and UK-2 offshore Niger Delta were subjected to biostratigraphic and organic geochemical analyses which entail foraminiferal, palynological, Spore Colour Index (SCI), Rock-Eval Pyrolysis and Fourier Transform Infrared Spectroscopy (FTIR) analyses. The results have established N19 and N17;N17, N16 and N15;and N9 and N8 biozones;and P600 and P700 palynological zones. The dominance of palynomaceral (PM) I and II suggests Type III kerogen. PM III and IV (Type II and IV) were recorded. SCI ranges from 3/4 to 5/6 suggesting an early to mature liquid hydrocarbon generation phase. Rock-Eval Pyrolysis shows that the Total Organic Carbon (TOC), Hydrogen Index (HI), Pyrolysis temperature (T<sub>max</sub>), and Vitrinite Reflectance (VR<sub>o</sub>) range from 2.48 wt% - 6.37 wt%, 78 - 258, 411°C - 431°C and 0.26% - 0.69% respectively suggesting high TOC of Type II/III kerogen. FTIR indices show Type I kerogen in all the wells. VRo results range from 0.4 - 0.5 indicating an immature source. High concentrations of aliphatic saturates in identified functional groups indicate a low biodegradation. The abundance and diversity of recovered assemblages and dominance of PM I and II suggest shallow depositional environments with an age range of late Miocene to early Pliocene. Palynomaceral, SCI, and Rock-Eval inference contradict FTIR kerogen type suggesting that IR spectroscopy might not be suitable for kerogen typing and origin. The geochemical and biostratigraphical inferences must be corroborated for a successful evaluation. However, the source rock in the study area has adequate organic matter with the prospect to generate both oil and gas at appropriate maturity. 展开更多
关键词 biostratigraphy ROCK-EVAL PALYNOFACIES Infrared Spectroscopy Palynomaceral
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Permian and Triassic Radiolarian Biostratigraphy in South and Southwest China 被引量:6
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作者 Feng QinglaiChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期55-66,129-130,共14页
The study of Permian radiolarias in South and Southwest China has been advanced in recent years . A well-preserved radiolarian fauna of Triassic is recently found in Southwest China . Eight radiolarian assemblage zone... The study of Permian radiolarias in South and Southwest China has been advanced in recent years . A well-preserved radiolarian fauna of Triassic is recently found in Southwest China . Eight radiolarian assemblage zones are recognized as follows in ascending order: Pseudoalbaillella rhombothoracata assemblage zone (Qixian ), Pseudoalbaillella fusiformis assemblage zone (early-middle Maokouan ), Follicucullus assemblage zone (late Maokouan-Wujiapingian ), Cangyuanella assemblage zone (early-middle Changxingian ), Clavata assemblage zone (latest Permian), Triassocampe yini assemblage zone (early Early Triassic ), Pseudoeucyrtis liui assemblage zone (late Early Triassic )and Triassocampe dew even assemblage zone (Middle Triassic ). The Permo -Triassic boundary in chert mono -facial sequence of the Muyinhe Formation is discussed . 展开更多
关键词 RADIOLARIA biostratigraphy Permian and Triassic South and Southwest China .
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Event Stratigraphy, Biostratigraphy and Sequence Stratigraphy of Neoproterozoic in North China 被引量:3
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作者 Qiao Xiufu Gao Linzhi Gao Mai Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037 《Journal of Earth Science》 SCIE CAS CSCD 1999年第2期3-11,共9页
The aim of this study is to discuss the chronostratigraphy, catastrophic event stratigraphy, biostratigraphy and sequence stratigraphy of Neoproterozoic. In the eastern part of the North China, the Neoproterozoic cons... The aim of this study is to discuss the chronostratigraphy, catastrophic event stratigraphy, biostratigraphy and sequence stratigraphy of Neoproterozoic. In the eastern part of the North China, the Neoproterozoic consists of Qingbaikou System (1 000-800 Ma) and Sinian System (800-600 Ma). The Qingbaikou System is widely distributed over the whole area and the Sinian System only in the eastern and southern parts of the plate. In this paper, we discuss the age limit of the formations, and try to establish the Neoproterozoic chronostratigraphic frame, the ages of which are partly based on recently obtained carbonate whole rock Pb Pb isotope. Based on the event records of ancient earthquake, which are well developed in Sinian carbonates, “a vibrational liquefaction seismic sequence” in carbonate rocks is established. We propose a time correlation for the Sinian formation in eastern North China, on the bases of event records of earthquake in combination with biostratigraphy, and thus revise the traditional correlation scheme that has been used for nearly 30 years. Some biostratigraphic results were obtained in fossil microplants, megafossils and metazoans in North China. A large amount of big double layered and complex ornamented acritarchs are found in Qingbaikou and Sinian systems. On the basis of the correlation by earthquake events, the Huainan fauna is regarded as Late Sinian, probably between 700 Ma and 600 Ma. Altogether 16 depositional sequences are distinguished in the Neoproterozoic, with an average time interval of about 15-16 Ma. 展开更多
关键词 catastrophic event stratigraphy biostratigraphy sequence stratigraphy NEOPROTEROZOIC North China.
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Uppermost Permian Radiolarian Biostratigraphy ofSouthern Guizhou, Southwest China 被引量:4
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作者 GuSongzhu FengQinglai 《Journal of China University of Geosciences》 SCIE CSCD 2002年第1期44-47,共4页
关键词 biostratigraphy RADIOLARIAN uppermost Permian Guizhou.
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Reexamination of Radiolarian Biostratigraphy in Permian in Pelagic Chert Sequences at Dachongling Section, South China 被引量:3
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作者 Sun Dongying Xia Wenchen Liu Dongjie Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2002年第3期207-214,共8页
Permian radiolarian biostratigraphy was reexamined in the bedded chertsection in Qinzhou area of southeast Guangxi Zhuang Autonomous Region, South China. On the basis ofthe analyses of characteristic radiolarian compo... Permian radiolarian biostratigraphy was reexamined in the bedded chertsection in Qinzhou area of southeast Guangxi Zhuang Autonomous Region, South China. On the basis ofthe analyses of characteristic radiolarian composition, six radiolarian zones are recognized,namely, Pseudoalbaillella longtanensis Zone, Pseudoalbaillella globosa Zone, Follicucullusmonacanthus Zone, Follicucullus scholasticus Zone, Follicucullus charveti Zone and Neoalbaillellaornithoformis Zone, in ascending order. Correlation of these radiolarian zones with those in Japanis presented. The Neoalbaillella ornithoformis Zone was firstly discovered in Dachongling Section,which may indicate that pelagic chert of the late Permian existed there, according to theco-occurring conodonts. 展开更多
关键词 PERMIAN pelagic chert radiolarian zones biostratigraphy
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The Maastrichtian-Danian in the SW Zagros Fold-Thrust Belt(S. Iran):An Integration of Planktonic Foraminiferal Biostratigraphy and Gamma-Ray Spectrometry 被引量:2
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作者 Abdolreza MOGHADDASI Hossein VAZIRI-MOGHADDAM Ali SEYRAFIAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第5期1339-1363,共25页
In this study, the Maastrichtian-Danian boundary was measured and sampled in two stratigraphic sections, the north and south flanks of the Dehnow anticline in Coastal Fars, Southern Iran. This boundary was also invest... In this study, the Maastrichtian-Danian boundary was measured and sampled in two stratigraphic sections, the north and south flanks of the Dehnow anticline in Coastal Fars, Southern Iran. This boundary was also investigated in the drilled exploratory well-1 in the same region. The lithology of the Maastrichtian-Danian deposits consists of glauconitic, phosphatic argillaceous limestones and marlstones. 30 genera and 77 species of planktonic foraminifera have been determined. The recognized biozones are the Gansserina gansseri Interval Zone, and the Contusotruncana contusa Interval Zone, which indicates latest Campanian to middle Maastrichtian age for the upper part of the Gurpi Formation. In addition, the Eoglobigerina edita(P1) Partial Range Zone, Praemurica uncinata(P2) Lowest Occurrence Zone, Morozovella angulata(P3) Lowest Occurrence Zone and Globanomalina psudomenardii(P4) Taxon Range Zone represent a Danian to Thanetian age for the lower part of the Pabdeh Formation. From the absence of the Abathomphalus mayaroensis Interval Zone, Pseudoguembelina hariaensis Interval Zone, Pseudotextularia elegans Interval Zone, Plummerita hantkeninoides Interval Zone, Guembelitria cretacea(P0) Partial Range Zone and Parvularugoglobigerina eugubina(Pα) Total Range Zone, it can be deduced that there is a paraconformity across the Maastrichtian–Danian boundary in the studied area, this hiatus encompassing the late Maastrichtian and the earliest Danian. Danian deposits from the study area contain reworked glauconitized macrofossils, planktonic and benthic foraminifera of the Cretaceous. The obtained surface gamma-ray spectrometry logs resemble the exploratory well-1 gamma-ray wireline log. 展开更多
关键词 biostratigraphy planktonic foraminifera gamma-ray spectrometry Maastrichtian-Danian ZAGROS Iran
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Cenozoic Calcareous Nannofossil Biostratigraphy of Sediments from Lingfeng Well in East China Sea 被引量:2
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作者 Su Xin Wu Fadong Center of Marine Geosciences, China University of Geosciences, Beijing 100083, China Zhou Pin Liu Jinshui Shanghai Offshore Petroleum Planning and Designing Institute, Shanghai 200093, China 《Journal of Earth Science》 SCIE CAS CSCD 2000年第3期65-69,共5页
A biostratigraphic study of calcareous nannofossils of sediments from Lingfeng No.1 well in the East China Sea was carried out to provide more detailed nannofossil data and a stratigraphic correlation among offshore ... A biostratigraphic study of calcareous nannofossils of sediments from Lingfeng No.1 well in the East China Sea was carried out to provide more detailed nannofossil data and a stratigraphic correlation among offshore wells located in the East China Sea.14 Paleocene to Pleistocene calcareous nannofossil zones were recognized based on a detailed examination. According to these nannofossil data, the Paleocene/Eocene and Pliocene/Pleistocene boundaries, as well as the Miocene base were determined.Oligocene NP23 and Miocene NN1 zones are firstly recognized by this study. The existence of Miocene NN1 at this well suggests that the Miocene transgression began in the Early Miocene in this area. The records of NP23 indicate that the marine Oligocene sediments exist in the series of Lingfeng wells, but probably as very thin layers. 展开更多
关键词 CENOZOIC calcareous nannofossils biostratigraphy offshore well East China Sea.
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Biostratigraphy and Paleoecology of Maastrichtian Sediments in the Zagros Basin, Iran 被引量:2
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作者 Mahnaz Parvaneh Nejad SHIRAZI Pegah SHAMS Mohammad BAHRAMI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1387-1395,共9页
To enable the lithostratigraphic and biostratigraphie study of the Gurpi Formation, within the 'Dezak' or Globigerina Marl, a stratigraphic section at Booraki, located to the NNW of Shiraz, SW Iran, through the late... To enable the lithostratigraphic and biostratigraphie study of the Gurpi Formation, within the 'Dezak' or Globigerina Marl, a stratigraphic section at Booraki, located to the NNW of Shiraz, SW Iran, through the late Cretaceous was examined. The formation consists of shale and greenish-gray marls interbedded with cream limestone, brown sandstones and siltstones with an exposed thickness of 160 m in the studied section. Samples were taken at regular intervals in all yielding 14 genera and 16 different species of benthic and planktic foraminifera that allowed determination of the age of the beds as Maastrichtian. To examine the paleoecology of the formation, some important ecological factors including water level, salinity, and oxygen regime change during the depositional courses of the formation were analyzed. The density of foraminiferans decreases from the base to top of the Gurpi Formation whereas the ratio of planktic to benthic Foraminifera (i.e., P/B) and proportion of shallow-water fauna increase. These foraminiferal changes indicate an increase and decrease in depth, temperature, salinity and oxygen, respectively, at the base and top of the Formation. 展开更多
关键词 biostratigraphy planktic/benthic foraminifera PALEOECOLOGY MESOZOIC Iran
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A New Mid Early Pleistocene Mammalian FaunaDiscovered in Choukoutien,China and Its Application in Biostratigraphy 被引量:2
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作者 Cheng Jie(Department of Geology and Mineral Resources, China University of Geosciences,Beijing 100083)Cao Boxun(Faculty of Earth Sciences, China University of Geosciences,Wuhan 430074)Tian MingZhong(Department of Geology and Mineral Resources, China Unive 《Journal of Earth Science》 SCIE CAS CSCD 1995年第1期41-47,120,共8页
This paper deals with a new Early Pleistocene micromammalian fauna found in Choukonden (Zhoukoudian) and its application in biostratigraphy.The new locality (east cave ), discovered in 1985,is located on the north slo... This paper deals with a new Early Pleistocene micromammalian fauna found in Choukonden (Zhoukoudian) and its application in biostratigraphy.The new locality (east cave ), discovered in 1985,is located on the north slope of the Taipingshan Hill, about 2 km northeast of the Loc.1 in Choukoutien and is about 140-150m in altitude. At this locality,abundant fossil mammals are found in thick cave-fissure deposit. This fauna comprises 30mammalian taxa. Based on the comparison of the fauna, as Well as the sporo-pollen, climate events and paleomagnetic polarity section with those in other areas,we come to the conclusion that the sediments (Taipingshan Formation) in east cave were formed during the Period about from 1.67 Ma B. P. to 0.97 Ma B. P., and the fauna is about 1.20 Ma B. P. in ags. 展开更多
关键词 mid Early Pleistocene micromammalian fauna biostratigraphy Choukoutien.
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Conodont Biostratigraphy and Age Determination of the Lower-Middle Triassic Boundary in South Guizhou Province,China 被引量:1
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作者 YAO Jianxin JI Zhansheng +6 位作者 WANG Liting WANG Yanbin WU Zhenjie LIU Dunyi WU Guichun ZHANG Jianwei LI Suping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第2期408-420,共13页
The demarcation of the Lower-Middle Triassic boundary is a disputed problem in global stratigraphic research. Lower-Middle Triassic strata of different types, from platform to basin facies,are well developed in Southw... The demarcation of the Lower-Middle Triassic boundary is a disputed problem in global stratigraphic research. Lower-Middle Triassic strata of different types, from platform to basin facies,are well developed in Southwest China. This is favorable for the study of the Olenekian-Anisian boundary and establishing a stratotype for the Qingyan Stage. Based on research at the Ganheqiao section in Wangmo county and the Qingyan section in Guiyang city, Guizhou province, six conodont zones have been recognized, which can be correlated with those in other regions, in ascending order as follows: 1, Neospathodus cristagalli Interval-Zone; 2, Neospathodus pakistanensis Interval-Zone; 3,Neospathodus waageni Interval-Zone; 4, Neospathodus homeri-N, triangularis Assemblage-Zone; 5,Chiosella timorensis Interval-Zone; and 6, Neogongdolella regalis Range-Zone. An evolutionary series of the Early-Middle Triassic conodont genera Neospathodus-Chiosella-Neogongdolella discovered in the Ganheqiao and Qingyan sections has an intermediate type named Neospathodus qingyanensis that appears between Neospathodus homeri and Chiosella timorensis in the upper part of the Neospathodus homeri-N, triangularis Zone, showing an excellent evolutionary relationship of conodonts near the Lower-Middle Triassic boundary. The Lower-Middle Triassic boundary is located at 1.5 m below the top of the Ziyun Formation, where Chiosella timorensis Zone first appears in the Qingyan section,whereas this boundary is located 0.5 m below the top of the Ziyun Formation, where Chiosella timorensis Zone first appears in the Ganheqiao section. There exists one nearly 6-m thick vitric tuff bed at the bottom of the Xinyuan Formation in the Ganheqiao section, which is usually regarded as a lithologic symbol of the Lower-Middle Triassic boundary in South China. Based on the analysis of high -precision and high-sensitivity Secondary Ion Mass Spectrum data ,the zircon age of this tuff has a weighted mean 206Pb/238U age of 239.0±2.9 Ma (2σ), which is a directly measured zircon U-Pb age of the Lower-Middle Triassic boundary. The Ganheqiao section in Wangmo county can therefore provide an excellent section through the Lower-Middle Triassic because it is continuous, the evolution of the conodonts is distinctive and the regionally stable distributed vitric tuff near the Lower-Middle Triassic boundary can be regarded as a regional key isochronal layer. This section can be regarded not only as a standard section for the establishment of the Qingyan Stage in China, but also as a reference section for the GSSP of the Lower-Middle Triassic boundary. 展开更多
关键词 L-M Triassic Qingyan Stage CONODONT biostratigraphy isotope chronology South China
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Larger Foraminiferal Biostratigraphy and Facies Analysis of the Oligocene–Miocene Asmari Formation in the Western Fars Sub-basin, Zagros Mountains, Iran 被引量:1
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作者 Tahereh HABIBI Telm BOVER-ARNAL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第6期2079-2097,共19页
The Oligocene–Miocene carbonate record of the Zagros Mountains, known as the Asmari Formation, constitutes an important hydrocarbon reservoir in southern Iran. This marine carbonate succession, which developed under ... The Oligocene–Miocene carbonate record of the Zagros Mountains, known as the Asmari Formation, constitutes an important hydrocarbon reservoir in southern Iran. This marine carbonate succession, which developed under tropical conditions, is explored in terms of larger foraminiferal biostratigraphy, facies analysis and sequence stratigraphy in a new section at Papoon cropping out in the western Fars sub-basin, in the south-east of the Zagros belt. Facies analysis shows evidence of re-working and transport of skeletal components throughout the depositional system, interpreted here as a carbonate ramp. The foraminifera-based biozones identified include the Globigerina–Turborotalia cerroazulensis–Hantkenina Zone and Nummulites vascus–Nummulites fichteli Zone, both of Rupelian age, the Archaias asmaricus–Archaias hensoni–Miogypsinoides complanatus Zone of Chattian age and the ‘Indeterminate’ Zone of Aquitanian age. The vertical sedimentary evolution of the formation exhibits a progressive shallowing of the facies belts and thus the succession is interpreted as a high-rank low-order regressive systems tract. This long-lasting Rupelian–Aquitanian regressive event is in accordance with accepted global long-term eustatic curves. Accordingly, long-term eustatic trends would have been a factor controlling accommodation during the deposition of the Asmari Formation studied in the western Fars sub-basin. 展开更多
关键词 larger foraminifera biostratigraphy sequence stratigraphy carbonate platform OLIGOCENE Zagros Basin Iran
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Calcareous Nannoplankton Biostratigraphy of the Bartin Province,Western Black Sea,Turkey 被引量:1
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作者 Caner Kaya OZER Vedia TOKER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1434-1446,共13页
Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostr... Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostratigraphy provides an age for the formation of the Early Campanian (nannofossil zone UC15aTp) to Early Selandian (nannofossil zone NPS), and highlights the presence of the Campanian/Maastrichtian, Cretaceous/Tertiary (K/T), and Danian/Selandian boundaries in this intermediate palaeolatitude location. Micula murus was identified below the K/T boundary, but Micula prinsii and Nephrolithus frequens were not, which implies that the K/T boundary interval is not complete in the study area. These dates are in agreement with previous micropaleontological studies. 展开更多
关键词 calcareous nannoplankton biostratigraphy CAMPANIAN MAASTRICHTIAN Danian Selandian
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Late Cretaceous-Early Paleogene Foraminiferal Biostratigraphy in Xishan,Gamba,Southern Tibet,China 被引量:1
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作者 HAN Yi LI Guobiao +9 位作者 LI Yuewei LI Xinfa WANG Tianyang XIE Dan ZHAO Shengnan ZHAO Jun ZHANG Jialin LI Qi CHEN Yu LI Na 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期106-108,共3页
1 Introduction The Cretaceous/Tertiary(Paleogene)extinction event was a mass extinction event occurring at about 65 million years ago between the Mesozoic Cretaceous and Cenozoic Tertiary,which is the one closest to t... 1 Introduction The Cretaceous/Tertiary(Paleogene)extinction event was a mass extinction event occurring at about 65 million years ago between the Mesozoic Cretaceous and Cenozoic Tertiary,which is the one closest to today among the five major extinction events in the the geological history period(Renne et al.,2013).At the end of the Cretaceous,the proportion of species declined gradually. 展开更多
关键词 FORAMINIFERA biostratigraphy K/T(Pg)boundary P/E BOUNDARY Gamba Tibet
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Late Cretaceous non-avian dinosaurs from the James Ross Basin,Antarctica:description of new material,updated synthesis,biostratigraphy,and paleobiogeography 被引量:1
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作者 Matthew CLAMANNA Judd ACASE +7 位作者 Eric MROBERTS Victoria MARBOUR Ricardo CELY Steven WSALISBURY Julia ACLARKE DEdward MALINZAK Abagael RWEST Patrick MO’CONNOR 《Advances in Polar Science》 CSCD 2019年第3期228-250,共23页
Although the fossil record of non-avian dinosaurs from the Cretaceous of Antarctica is the poorest of any continent,fossils representing at least five major taxonomic groups(Ankylosauria,early-diverging Ornithopoda,Ha... Although the fossil record of non-avian dinosaurs from the Cretaceous of Antarctica is the poorest of any continent,fossils representing at least five major taxonomic groups(Ankylosauria,early-diverging Ornithopoda,Hadrosauridae,Titanosauria,and Theropoda)have been recovered.All come from Upper Cretaceous(Coniacian–Maastrichtian)marine and nearshore deposits belonging to the Gustav and Marambio groups of the James Ross Basin at the northern tip of the Antarctic Peninsula.The majority of these finds have come from the Campanian–Maastrichtian Snow Hill Island and López de Bertodano formations of James Ross and Vega islands.Given the rarity of Antarctic Cretaceous non-avian dinosaurs,discoveries of any fossils of these archosaurs,no matter how meager,are of significance.Here we describe fragmentary new ornithischian(ankylosaur and ornithopod)material from the upper Campanian–lower Maastrichtian Cape Lamb Member of the Snow Hill Island Formation and the Maastrichtian Sandwich Bluff Member of the López de Bertodano Formation.One of these specimens is considered to probably pertain to the holotypic individual of the early-diverging ornithopod Morrosaurus antarcticus.We also provide an up-to-date synthesis of the Late Cretaceous non-avian dinosaur record of the James Ross Basin and analyze the biostratigraphic occurrences of the various finds,demonstrating that most(including all named taxa and all reasonably complete skeletons discovered to date)occur within a relatively condensed temporal interval of the late Campanian to early Maastrichtian.Most or all James Ross Basin dinosaurs share close affinities with penecontemporaneous taxa from Patagonia,indicating that at least some continental vertebrates could disperse between southern South America and Antarctica during the final stages of the Mesozoic. 展开更多
关键词 Dinosauria ANTARCTICA Cretaceous JAMES ROSS BASIN biostratigraphy PALEOBIOGEOGRAPHY
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Biostratigraphy and Paleoecological Study of Pabdeh Formation in Interior Fars, Zagros Basin, Iran 被引量:2
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作者 Manooseh P. Khavari Khorassani Fatemeh Hadavi +1 位作者 Ebrahim Ghasemi-Nejad Reza Mousavi-Harami 《Open Journal of Geology》 2014年第11期571-581,共11页
The Zagros basin, which trends NW-SE, is covered by a sea during the Paleogene, resulting in deposition of the Pabdeh Formation in the deeper parts of the basin. The thickness of the Pabdeh Formation in Tang-e-Abolhay... The Zagros basin, which trends NW-SE, is covered by a sea during the Paleogene, resulting in deposition of the Pabdeh Formation in the deeper parts of the basin. The thickness of the Pabdeh Formation in Tang-e-Abolhayat is about 221 m and it consists of purple shale at the base, gray shale, marl and marly limestone with a few horizons of nodular limestone toward the top. Seventy-two samples were collected and processed for nannofossil studies. Based on the identified nannofossil zones the age of the formation in Tang-e-Abolhayat is Late Paleocene-Late Oligocene (NP9-NP24). Changes in the abundance of different genera over the studied interval have resulted in identification of three ecozones: Ecozone 1 is characterized by oligotrophic conditions with an abundance of warm water taxa;Ecozone 2 marks when conditions became more eutrophic and the abundance of temperate taxa increased;Ecozone 3 represents a return to oligotrophic conditions with an increase in warm water taxa. 展开更多
关键词 biostratigraphy Pabdeh FORMATION ZAGROS Ecozone NANNOFOSSIL
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Aptian biostratigraphy in South Zagros Basin, southwest Iran 被引量:2
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作者 Massih Afghah Arash Shaabanpour Haghighi 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第2期277-288,共12页
The Khami group within the petroliferous Zagros Basin of Iran includes the Surmeh, Hith, Fahliyan, Gadvan and Dariyan formations. The Dariyan Formation, previously known as Orbitolina limestone is very signif-icant as... The Khami group within the petroliferous Zagros Basin of Iran includes the Surmeh, Hith, Fahliyan, Gadvan and Dariyan formations. The Dariyan Formation, previously known as Orbitolina limestone is very signif-icant as a reservoir rock in the Zagros Basin. In this study, the age of the Dariyan Formation is examined based on biostratigraphic and paleontological investigations. 236 m of Dariyan Formation sediments in the sections at Kuh-e Rahmat (north) and Nour-Abad (west) of Iran were selected to study its biostratigraphy. According to the lithostratigraphic investigations, the Dariyan Formation in these sections is subdivided into three: lower, middle and upper, which include thin-bedded to medium-bedded and massive lime-stone. Micropaleontologic study of the Dariyan Formation has led to the recognition of two biozones in the Nour-Abad area and one biozone in the Kuh-e Rahmat stratigraphic column. Diagnostic foraminifera in these sections are as follows: Globigerinel oides algerianus Cushman and Ten Dam, Globigerinelloides fer-reolensis Moullade, Globigerinelloides maridalensis (Bolli), Globigerinelloides paragottisi Verga and Permoli Silva, Hedbergel a aptiana Bartenstein, Hedbergel a excelsa Longoria, Hedbergel a luterbacheri Longoria, Hedbergella occulta Longoria, Hedbergella ruka (Banner et al.), Hedbergella similis Longoria, Hedbergella trocoidea (Gandolfi), Muricohedbergella delrioensis (Carsey), Pseudoplanomalina cheniourensis Sigal, Con-icorbitolina conica d'Archiac, Iraqia sp., Mesorbitolina parva Douglass, Mesorbitolina pervia Douglass, Meso-rbitolina ovalis Gorog and Arnaud-Vanneau, Mesorbitolina subconcava Leymerie, Mesorbitolina texana (Roemer), Mesorbitolina ovalis-pervia Cherchi and Schroeder, Debarina hahounerensis Fourcade et al., Marssonel a trochus (d'Orbigny), Nezzazata sp., Orbitolina sp., Textularia sp. 展开更多
关键词 Aptian biostratigraphy Foraminifera Zagros Fars Iran
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Tertiary Calcareous Nannofossil Biostratigraphy in the North Part of the South China Sea 被引量:1
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作者 Duan Weiwu and Huang Yongyang Gangzhou Marine Geological Survey, Ministry of Geology and Mineral Resources, Guangzhou Chang Zhijun and Sun Sheping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1991年第3期321-338,343-344,共20页
The marine Tertiary sequence in the north part of the South China Sea may be divided into 18 LateOligocene to Pliocene calcareous nannofossil zones and one unnamed Eocene assemblage based on an analysisof calcareous n... The marine Tertiary sequence in the north part of the South China Sea may be divided into 18 LateOligocene to Pliocene calcareous nannofossil zones and one unnamed Eocene assemblage based on an analysisof calcareous nannofossils from 40 offshore boreholes. The unnamed Eocene assemblage has been found onlyon the northeast margin of the Zhujiangkou basin. The 18 cakareous nannofossil zones of the Late Oligoceneto Pliocene were deposited in succession, but their development degrees are different. Among the 18 calcareousnannofossil zones, those corresponding to Martini's (1971) NN4- NN5 zones, NN11 zone and NN13-NN15zones are well developed, relatively persistent laterally and also widely distributed. They are the importantmarkers for the stratigraphical subdivision and correlation of the Upper Tertiary between the various basins inthe north part of the South China Sea. Based on the calcareous nannofossils and the sedimentsry features coup-led with the foraminifer zonation in certain basins, the present paper discusses the sedimentary characteristicsof the marine Tertiary and as well as the distribution and development of the sedimentary hiatus in the region.The calcareous nannofossil markers for the Upper / Lower Tertiary and the Quaternary / Tertiary boundaries,and the characteristics and geological significance of the reworked calcareous nannofossils are also discussed inthe paper. 展开更多
关键词 Tertiary Calcareous Nannofossil biostratigraphy in the North Part of the South China Sea
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Biostratigraphy and Sequence Stratigraphy of the Tarbur Formation(Maastrichtian)from Iranian Zagros Foreland Basin,Southwest of Iran
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作者 Hossein GHANBARLOO Amrollah SAFARI Hossein VAZIRI-MOGHADDAM 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第1期147-166,共20页
Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian age.From the viewpoint of reconstruction of depositional conditions in these deposit... Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian age.From the viewpoint of reconstruction of depositional conditions in these deposits,studies of biostratigraphy,microfacies,microtaphofacies,and sequence stratigraphy were performed in a single area at Tang-e Shabi Khoon,northwest of Zagros.Based on the identification of two assemblage zones consisting of benthic foraminifera in these strata,the formation was deposited during the middle to late Maastrichtian.The number of cycles in test size and type of coiling in Loftusia decreased from the study area toward the northwest of the Neotethys basin.The input of clastic sediments affected the distribution of Loftusia and rudists in the study area.Nine microfacies,six microtaphofacies,and one terrigenous facies(shale)were identified based on the sedimentary features.These deposits of the middle-late Maastrichtian were deposited on a homoclinal carbonate ramp.The platform can be divided into restricted and semi-restricted lagoon,shoal,and open marine environments.In the study area,the deposits of the Tarbur Formation were deposited during four third-order depositional sequences.Local fault activities affected the formation of depositional sequences in the study area. 展开更多
关键词 biostratigraphy MICROFACIES microtaphofacies rudist patchy reef ramp Tarbur Formation MAASTRICHTIAN
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Biostratigraphy,Microfacies and Depositional Environment of the Sarvak Formation at the Pyun Anticline(Zagros Basin,Southwest of Iran)
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作者 Mahtab DOUSTI MOHAJER Massih AFGHAH +1 位作者 Mohammadsadegh DEHGHANIAN Seyed Jamal SHEIKH ZAKARIAII 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第5期1647-1667,共21页
The Sarvak Formation is a carbonate sequence of Late Albian–Early Turonian age in Zagros Basin in Iran.In this investigation,the Sarvak Formation at the Pyun Anticline section(Izeh Zone)has been studied.It consists o... The Sarvak Formation is a carbonate sequence of Late Albian–Early Turonian age in Zagros Basin in Iran.In this investigation,the Sarvak Formation at the Pyun Anticline section(Izeh Zone)has been studied.It consists of 797 m thick limestone which overlies the Kazhdumi Formation conformably and underlies the Gurpi Formation unconformably at the Pyun Anticline.A very rich fossil association(85 genera and 132 species)characterizes the Pyun section.Based on the stratigraphic distribution of diagnosed foraminifera,five biozones are established:1,Muricohedbergella-Globigerinelloides sp.assemblage zone(Late Albian);2,Praealveolina iberica-Chrysalidina gradata interval zone(Early Cenomanian);3,Chrysalidina gradata-Cisalveolina fraasi(fallax)and C.lehneri interval zone(Middle Cenomanian);4,C.fraasi(fallax)and C.lehneri-Praetaberina bingistani assemblage zone(Late Cenomanian);5,Nezzazatinella picardi-MangashtiaDicyclina assemblage zone(Early Turonian).Based on the petrographic and sedimentological analyses,some 13 carbonate microfacies were identified.The investigated microfacies confirm a ramp-type paleoenvironment.These microfacies,from distal to proximal environments,consist of:MF1:planktonic foraminifera wackestone-packstone;MF2:Oligostegina planktonic foraminifera wackestone to packstone;MF3:planktonic-benthic foraminifers sponge spicules wackestonepackstone;MF4:rudist floatstone;MF5:rudist rudstone;MF6:bioclast intraclast grainstone;MF7:peloid intraclast grainstone;MF8:benthic foraminifers rudist grainstone-packstone;MF9:peloid bioclast grainstone-packstone;MF10:bioclast(benthic foraminifers)wackestone-packstone;MF11:peloid bioclast packstone;MF12:dacycladacea benthic foraminifera packstone-wackestone;MF13:miliolids wackestone-packstone. 展开更多
关键词 Sarvak Formation biostratigraphy MICROFACIES Pyun Izeh Zone Zagros Basin
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