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Acta Geologica Sinica(English Edition) 2024年第4期98卷 1021-1034页

作者： Caner KAYAÖZER Muazez Esra ORHAN Uğur TEMİZ Yozgat Bozok University DivanlıRoadYozgat 66900Turkey

This study investigated the calcareous nannofossil assemblages in detail from the early Miocene aged Lice Formation outcropping in the Kahramanmara? basin. The biostratigraphy of calcareous nannofossils was outlined and paleoenvironmental features determined. In 81 samples taken from three measured sections in the region, 17 calcareous nannofossil genus and 48 nannofossil species were identified. These calcareous nannofossil genus and species identified the Lice Formation as being in the CNM4 nannofossil biozone. The abundance and diversity of early Miocene calcareous nannofossil species varied in the measured sections, with the samples generally moderate-poor, apart from a few samples. The relative abundance of individuals of Cyclicargolithus floridanus, Coccolithus pelagicus, Reticulofenestra hagii and Sphenolithus moriformis species, with paleoecological importance identified in the study region, indicate that in early Miocene times, the basin in which the Lice Formation deposited was meso-eutrophic with excess nutrient input, temperate and generally stable shallow marine conditions.

关键词： paleoecology nannofossil Burdigalian East Mediterranean

Calcareous nannofossil changes linked to climate deterioration during the Paleocene-Eocene thermal maximum in Tarim Basin,NW China

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Geoscience Frontiers 2018年第5期9卷 1465-1478页

作者： Wenxin Cao Dangpeng Xi Mihaela C.Melinte-Dobrinescu Tian Jiang Sherwood W.Wise Jr. Xiaoqiao Wan State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China National Institute of Marine Geology and Geo-ecology(GEOECOMAR) Bucharest 70318Romania Department of Earth Ocean&Atmospheric ScienceFlorida State UniversityTallahasseeFL 32306United States

The Paleocene-Eocene Thermal Maximum(PETM) event was a dramatic global warming w55.93 Ma ago that resulted in biological extinction events, lithological changes, and major deviations in σ13 C and σ18 *** southwestern Tarim Basin of China exposes successive Paleogene strata as a result of Tethys evolution and is considered an ideal region for PETM *** on calcareous nannoplankton biostratigraphy, we also used stable isotopes and XRD to analyse the Paleocene-Eocene transition in the Tarim Basin. At the Bashibulake Section, the PETM interval is characterized by(1) an abrupt negative shifts in σ13 C_(org), σ13 C_(carb) and σ18 O(-3%, -4.5% and -3%respectively);(2) an obvious negative correlation between the K-mode(Discoaster, Fasciculithus, Ericsonia, Sphenolithus and Rhomboaster) and r-mode(Biscutum, Chiasmolithus, Toweius) nannofossil taxa coincident with a robust Rhomboaster-Discoaster assemblage; and(3) a significant increase in the percentage of detrital input along with an increase in gypsum content. In the upper part of the Qimugen Formation Micrantholithus and Braarudosphaera are commonly found right up to the top where most of the nannofloras suffer a sharp decrease. In the overlying Gaijitage Formation, calcareous nannofossils disappear completely. These events indicate that the southwestern Tarim Basin was a warm shallow continental shelf during the deposition of the Qimugen Formation. From the early Eocene, the environment changed conspicuously. Evaporation increased and sea level fell, which led to an acid *** climate mode continued within the youngest unit studied, the Gaijitage Formation, characterized by the deposition of thick evaporates. Consequently, most of the marine plankton, i.e. calcareous nannoplankton, became disappear, because of the significant climate shift.

关键词： Calcareous nannofossil Biostratigraphy Paleocene-Eocene Thermal Maximum(PETM) Tarim Basin

Variations in late Quaternary upper ocean structure of Okinawa Trough:A nannofossil approach

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Science China Earth Sciences 1998年第3期41卷 290-296页

作者：成鑫荣汪品先

The relative abundance of Florisphaera profunda , a calcareous nannofossil species in lower euphotic zone, affords an opportunity to study variations in upper ocean structure such as thickness of mixed layer. As revealed by the nannofossil analysis in sediments since 20 ka B.P. from three Okinawa Trough cores, the percentage of F. profunda increased significantly from glacial to Holocene, with a declining event ca 4 ka B.P. in its southern part. Its downcore trend is similar to that of Pulleniatina obliquiloculata, a tropical planktonic foraminiferal species which lives in subsurface water below thermocline in the modern ocean. Their similar variations imply an eastward shift of the Kuroshio Current, a reduction in thickness of the mixed layer, a shallowing of thermocline and a possible increase of turbidity in the upper ocean during the glaciation. The eastward shift of the Kuroshio might be repeated again about 4 ka B.P.

关键词： upper ocean Okinawa Trough calcareous nannofossil nutricline thermocline.

Sea-Surface Dynamics Changes in the Subpolar North Atlantic Ocean (IODP Site U1314) during Late Pliocene Climate Transition Based on Calcareous nannofossil Observation

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Open Journal of Geology 2017年第10期7卷 1538-1551页

作者： Resti Samyati Jatiningrum Tokiyuki Sato Department of Geosciences Geotechnology and Materials Engineering for Resources Akita University Akita Japan Faculty of International Resources Sciences Akita University Akita Japan

Calcareous nannofossils were observed to reconstruct the surface water conditions during late Pliocene climate transition (2.55 to 2.88 Ma) from the southern Gardar Drift, in the subpolar North Atlantic IODP Site U1314 (56°21.9’1N, 27°53.3’W). A total of 24 species from 14 genera were identified by polarizing microscope observation. The coccolith assemblages are dominated by species belonging to genus Reticulofenestra with different (size-defined) morphotype. Hence, changes in paleoceanographic condition are shown by the size variation of Reticulofenstraspecimens. Before ~2.76 Ma, the studied interval is characterized by the presence of an abundant larger Reticulofenstra group. It indicates warm oligotrophic and stable surface waters. At ~2.76 Ma the abundance of large Reticulofenstra decreased abruptly and alternated with small Reticulofenstra, suggesting collapse of sea surface stability with strong mixing condition. This event coeval with the final closure of the Central American Seaway (CAS) and the onset of intensified North Hemisphere Glaciation (NHG). Subsequently, the size variation of Reticulofenestra specimens exhibits a sequential pattern that is somewhere consistent with the interglacial-glacial cycle. The pattern begins with a gradual increase in size upward during interglacial suggesting warm oligotrophic and stable condition, and ends with an abrupt decrease in coccolith size during glacial suggesting eutrophic or strong mixing condition and destabilized sea surface waters.

关键词： Late Pliocene Sea-Surface Waters Conditions Calcareous nannofossil Subpolar North Atlantic

Calcareous nannofossil Biostratigraphy and Stage Boundaries of the Santonian-Eocene Successions in Wadi El Mizeira Northeastern Sinai, Egypt

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International Journal of Geosciences 2014年第4期5卷 432-449页

作者： Hamza Khalil Esam Zahran Geology Department Faculty of Science Damanhour University Damanhour Egypt Geology Department Faculty of Science Tanta University Tanta Egypt

The stratigraphic successions exposed in Wadi El Mizeira have been dated through the analysis of the calcareous nannofossil assemblages. The results of this study indicate that the successions comprise the Santonian-Late Maastrichtian (Sudr Formation), the Paleocene (Esna Formation) and the Early Eocene (Thebes Formation). The following biozones were recognized: Late Santonian, CC16 Zone;Late Santonian/Early Campanian, CC17 Zone;Early Campanian, Aspidolithus parcus Zone (CC18) Zone;Late Maastrichtian, CC25c Zone;Early Paleocene (Late Danian), NP3 Zone and NP4 Zone;Late Paleocene (Thanethian-Selandian), NP5 Zone;Early Eocene, NP9b Zone, NP10a Zone, NP11 Zone, NP12 Zone and NP14 Zone. Several stratigraphic hiatus were recorded in the studied interval including the absence of Cretaceous nannofossil Zones CC19 to CC25b and CC26 as well as the early Paleocene Zones NP1 and NP2 and probably the basal part of Zone NP3, in addition to the absence of the Zones NP6 and NP7/8. These hiatus may be attributed to environmental conditions, structural activity and/or post depositional processes. This work represents the first attempt to evaluate the nannofossil taxa of the Wadi El Mizeira, Northeastern Sinai.

关键词： Calcareous nannofossil Biostratigraphy Santonian Eocene Sinai Egypt

Oxygen and carbon isotope records of calcareous nanno-fossils for the past 1 Ma in the southern South China Sea

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Chinese Science Bulletin 2002年第10期47卷 798-803页

作者： LIU Chuanlian CHENG Xinrong ZHU Youhua TIAN Jun XIA Peifen Key Laboratory of Marine Geology of Ministry of Education Tongji UniversityShanghai 200092China Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjing 210008China

Oxygen and carbon isotopic analyses have been carried out on calcareous nannofossils from ODP Site 1143 in the southern South China Sea. The results demonstrate that the δ18O values of calcareous nannofossils for the past 1 Ma vary systematically with those of planktonic and benthic foraminifera from the same site. But the average δ18O value of nannofossils is 1.869‰ higher than that of planktonic foraminifera, and is 3.855‰ lower than that of benthic foar-minifera. There are systematic differences between the δ13C values of nannofossils, planktonic foarminifera and benthic foraminifera. The average δ13C of nannofossils is 0.756‰ higher than that of benthic foraminifera, and is 0.460‰ lower than that of planktonic foraminifera. The δ13C values of nannofossils exhibit a significant positive shift beginning near isotope stage 14 and lasting until stage 8. This study also finds that there is a close ralationship between the δ13C of nannofossils and the percentage of Florisphaera profundo. This

关键词： oxygen and carbon isotope calcareous nannofossil South China Sea.

Late Quaternary Calcareous nannofossils from the Offshore Sediments in southern Hongkong

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Acta Geologica Sinica(English Edition) 1999年第2期73卷 242-247页

作者： HUANG Yongyang CHEN Fang Guangzhou Marine Geological Survey MGMR Guangzhou 510075

Abstract Based upon the features of nannofossil composition, distribution, abundance and diversity, the fossil-bearing sediments exposed by five drill holes in the offshore area of southern Hongkong can be divided into the upper Middle Pleistocene, the Upper Pleistocene and Holocene. There were two palaeoclimatic stages in the Holocene in this area according to fossil palaeoecologic and sedimentation analyses: the temperature-rising stage and the warm stage. The latter involves two temperature-falling periods, which could be the major factor causing sea-level fall during that time.

关键词： nannofossil Quaternary palacooceanography Lingdingyang southern Hongkong

An Integrated Wireline-Log and Biostratigraphic Appraisal of Olure-1 and Abigboro-1 Wells, Onshore Niger Delta

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Open Journal of Geology 2017年第8期7卷 1140-1159页

作者： Olugbenga A. Boboye Abdulkarim S. Oladayo Emmanuel E. Okon Department of Geology University of Ibadan Ibadan Nigeria Department of Geology University of Calabar Calabar Nigeria

Studies of two wells within the coastal swamp onshore Niger Delta were carried out in order to determine the chronology, biozonation, and establishment of sequence stratigraphic framework for the representative wells. A total of twenty-eight (28) cutting samples were recovered and analysed from Abigboro-1 and Olure-1 exploratory wells for their foraminifera, calcareous nannofossils and palynomorphs’ compositions. The results indicated the presence of diverse species within the wells, which include Lenticulina grandis, Florilus ex. gr. costiferum, Hanzawaia concentrica, Hopkinsina bononiensis, Marginulina costata and pseudonodosaria sp., Bolivina mandoroveensis, Eponides eshira, Lenticulina grandis, Lenticulina grandis, Cibicorbis inflata, Heterolepa floridana, Florilus ex. gr scaphum, Poroeponides lateralis, Uvigerina sparsicostata, Uvigerina subperegrina, Bolivina ex. gr. scalptrata, Valvulineria sp. and Epistominella pacifica. An inner neritic (1694 m - 2161 m), coastal deltaic (1557 m - 1640 m) and shallow inner neritic (1347 m - 1554 m) palaeoenvironment was suggested for Olure-1 well while a broad grouping of the intervals as inner to middle neritic was suggested for Abigboro-1 well. The ratio of species abundance/diversity and integration of log suite data predicted two Maximum Flooding Surfaces (MFS) and one Sequence Boundary (SB) for Olure-1 well. The MFS were encountered at depths 2728 m (MFS 1) and 1797 m (MFS 2), while the SB was predicted at depth 2602 m (SB1). Diverse systems’ tracts were identified and delineated from wireline logs of Olure-1 well and the implication for petroleum exploration was discussed. Late Oligocene - early Miocene age has been assigned for the wells based on the recovered diagnostic species.

关键词： Species Palaeoenvironment Palynomorphs nannofossil Biozonation

Biostratigraphy and Paleoecological Study of Pabdeh Formation in Interior Fars, Zagros Basin, Iran

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Open Journal of Geology 2014年第11期4卷 571-581页

作者： Manooseh P. Khavari Khorassani Fatemeh Hadavi Ebrahim Ghasemi-Nejad Reza Mousavi-Harami Departement of Geology Faculty of Science Ferdowsi University of Mashhad Mashhad Iran Department of Geology Faculty of Sciences University of Tehran Tehran Iran

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.

关键词： Biostratigraphy Pabdeh Formation Zagros Ecozone nannofossil

Facies and Sequence Stratigraphy Analyses of Klasaman Formation in the “X Well”, Northern Salawati Basin, Papua, Indonesia

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Open Journal of Geology 2018年第5期8卷 499-513页

作者： Ovinda Edy Sunardi Ahmad Helman Hamdani Muhammad Burhannudinnur Afriadhi Triwerdhana Faculty of Geological Engineering Universitas Padjadjaran Bandung Indonesia Faculty of Earth Technology and Energy Universitas Trisakti Jakarta Indonesia KTI Exploration Pertamina EP Jakarta Indonesia

The “X Well” is located in the Salawati Basin which is part of Western Papua. The interval of study is the Klasaman Formation that is characterized by thick sediment intercalated sandstones and shales. The movement of Sorong Fault strongly controlled the sedimentation of this formation. This study is very important to give a contribution for developing exploration prospect by predicting reservoir distribution since localized facies change may mark the distribution of sandstones. The current study aims: 1) to define the age of Klasaman Formation;2) to define the vertical facies;3) to define the sequence stratigraphy;and 4) to predict the lateral change of facies. Five nannofossil datum planes are found throughout the interval and cover the age Late Miocene to Early Pliocene. LO Sphenolithus abies points the age 3.65 Ma, LO Reticulofenestra pseudoumbilicus points the age 3.79 Ma, FO Pseudoemiliania lacunosa points the age 4 Ma, LO Discoaster quinqueramus and LO Discoaster berrgrenii point the age 5.59 Ma and Top of small Reticulofenestra Interval points the age 7.167 Ma. They define the NN11 up to NN16 Martini’s zonation. The age of Klasaman Formation is known as the uppermost Late Miocene to the Early Pliocene. Four facies can be identified, namely Upper Shoreface, Lower Shoreface, Offshore Transition and Offshore. The upper shoreface facies is characterized by thick and clean sandstones, about 2.41 - 20.64 meters thick, while the lower shoreface facies consists of predominantly very fine to fine-grained sandstones intercalated by siltstones and claystones. The offshore transition facies is marked by thick claystones and siltstones intercalated with thin sandstones, whilst the offshore facies is marked by thick laminated claystones. Nine Parasequences 4th order can be identified within study interval, namely Progradational Parasequence-1 to 2, Retrogradational Parasequence-3, Progradational Parasequence-4 to 6, Retrogradational Parasequence-7 to 9. They are bounded b

关键词： Salawati Basin nannofossil Age Facies Sequence Stratigraphy and Sorong Fault