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foraminifera in Cenozoic Paleoenvironments

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Journal of China University of Geosciences 2005年第3期16卷 200-218页

作者： Brian Mc Gowran School of Earth & Environmental Sciences Mawson Building DP313 The University of Adelaide Adelaide SA 5005 Australia

Paleontologists search the fossil record for evidence of age, ancient environments, phylogenetic reconstructions and ancient communities. Cenozoic foraminifera preserve evidence for all of these simultaneously from the water column and from at, above and below the sediment/water interface. As our understanding of foraminiferal assemblages and their place in the strata （biofacies） becomes more sophisticated, so are foraminiferal biofacies challenged to contribute to more subtle problems in Cenozoic earth and life history. Progress is described as a series of five ＂integrations＂. （Ⅰ） The quantification of foraminiferal biofacies was an advance on simple presences and absences of species meeting such questions as marine or nonmarine, or shallow or deep. （Ⅱ） foraminiferal shells carry geochemical signals especially isotopes of oxygen （temperature, ice volume）, carbon （nutrition and the carbon cycle）, and strontium （seawater ratios through time）. （Ⅲ） From modern foraminiferal biology we have lifestyle insights leading to a model of oceans and paleo-oceans called the trophic resource continuum, a valuable way into greenhouse-icehouse comparisons and contrasts. （Ⅳ） Biofacies changes in space and time are sometimes abrupt with little evidence of diachrony, and sometimes gradual. These patterns are clarified in the context of sequence stratigraphy （which they enrich in turn）. （Ⅴ） The paleobiological counterpart of sequence stratigraphy is evolutionary paleoecology, reconstructing communities in deep time. The foraminifera are perfectly suited to investigate the possibility （or likelihood） that global environmental shifts have controlled community turnover in the pelagic, neritic and terrestrial realms.

关键词： foraminifera biofacies stratigraphy paleoecology paleoenvironment evolution Cenozoic trophic resource continuum

Morphology of four Miliolinella species (foraminifera, Protozoa) with description of a new species, Miliolinella obesa nov. spec., from the tropical West Pacific Ocean

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Acta Oceanologica Sinica 2018年第10期37卷 64-69页

作者： LEI Yanli LI Tiegang Department of Marine Organism Taxonomy and Phylogeny Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Key Laboratory of Marine Sedimentology and Environmental Geology the First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology (Qingdao) Qingdao 266061 China Center for Ocean Mega-Science Chinese Academy of Sciences Qingdao 266071 China University of Chinese Academy of Sciences Beijing 100049 China

foraminiferal oozes were sampled from the tropical West Pacific seamount and seabed of deep sea, by a remotely operated vehicle （ROV） in December 2014 and March 2016. Using standard morphological method, four Miliolinella species, including Miliolinella obesa, M. circularis, M. suborbicularis and M. subrotunda were described. Among the four species, M. obesa is a new species. It is a large member （about 500 μm in length） of the genus. This species is characterized by having a very stout and transverse broadly circular outline, and its body width is greater than the body length. In addition, its chamber demarcations are obscure from the exterior appearance. Three chambers are unclearly visible on one side and two chambers are visible on the opposite. Finally, we provided very detailed taxonomic microphotographs and the ecological distribution information for each species.

关键词： deep sea foraminifera Miliolinella seamount seabed West Pacific Ocean

The earliest foraminifera from southern Shaanxi,China

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Science China Earth Sciences 2010年第12期53卷 1756-1764页

作者： HUA Hong CHEN Zhe YUAN XunLai XIAO ShuHai CAI YaoPing Early Life Institute State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest UniversityXi’an710069China Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjing 210008China Department of Geosciences Virginia Polytechnic Institute and State UniversityBlacksburgVirginia24061USA

Vase-shaped microfossils(VSMs) described herein mainly occur as isolated individuals in thin bedded siltstone and silty carbonate of the Gaojiashan Member of the upper Ediacaran Dengying Formation(ca.551-541 Ma).Although these fossils are abundant,chained tests or other types of colonial aggregates have not been *** in the siltstones can easily be isolated from the host rocks by ultrasonic *** with the co-occurring fossils Gaojiashania and Conotubus,VSMs are rarely pyritized,yet they are always three-dimensionally persevered with little deformation,suggesting that their tests were sturdy and possibly *** observation and elemental mapping reveal two types of tests that are respectively calcareous and siliceous in *** tests typically consist of two to three crypto-crystal laminae,somewhat resembling bilamellar walls of *** tests consist of fine-grained particles agglutinated with siliceous cement,similar to agglutinated walls of *** Gaojiashan VSMs are broadly similar,at least in gross morphology,to the testate amoebae-like VSMs,but their relative large sizes(600-2400 μm) and possibly mineralized(rather than organic) tests argue against this *** also show some similarities to other protozoans,especially ***,tintinnids have robust pesudochitinous loricae consisting of both secreted and agglutinated ***,tintinnid loricae differ in shape from the Gaojiashan VSM tests in having a constricted aboral end(sometimes with a caudal appendix) and a flaring oral *** the Gaojiashan VSMs are indeed related to foraminifers,they indicate that foraminifers were important players in late Ediacaran communities.

关键词： Gaojiashan biota vase-shaped microfossils foraminifera

Molecular biological research on foraminifera

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Progress in Natural Science:Materials International 2005年第8期15卷 673-677页

作者： Kemal Topac ERTAN,Christoph HEMLEBEN Institute and Museum of Geology and Paleontology University of Tuebingen D-72076 Tuebingen Germany Institute and Museum of Geology and Paleontology University of Tuebingen D-72076 Tuebingen Germany

As one of the most important groups in micropaleontology, foraminifera is traditionally described to have a membranous, agglutinated or carbonate shell according to its morphology, which resembles the marine granuloreticuloseans. However, recent molecular analyses on its ribosomal RNA gene have disclosed the existence of the naked, and also freshwater and terrestrial species. foraminiferal SSU rDNA sequence suggests that this group is positioned at the base of the Eukaryotes phylogenetic trees, between Euglenoida and Diplomonadida. Existence of a large amount of genetic types in planktonic foraminifera suggests an underestimation of the biodiversity for the nearly 50 species in world oceans and their close relationship with the ocean environment, such as bio-geographic distribution and water currents. This provides a more reliable proxy for future paleoenvironmental study.

关键词： foraminifera ribosomal DNA molecular biology phylogeny paleoceanography.

Secondary Calcification of Planktic foraminifera from the Indian Sector of Southern Ocean

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 27-37页

作者： Rahul MOHAN Suhas S.SHETYE Manish TIWARI Narayanpillai ANILKUMAR National Centre for Antarctic and Ocean Research National Institute of Oceanography

This study focused on planktic foraminifera in plankton tows and surface sediments from the western Indian sector of Southern Ocean in order to evaluate the potential foraminiferal secondary calcification and/or dissolution in the sediment. It is found that the symbiotic foraminiferal species are abundant in the subtropical region, whereas non-symbiotic species dominate in the sub-Antarctic and polar frontal regions. The distribution of the symbiotic and non-symbiotic foraminiferal species is controlled by temperature, salinity, light, nutrients and phytoplankton biomass. There is also a lateral southern extent in abundance of planktic foraminifera from surface sediments to plankton tows. The shell weights of the planktic foraminifera N. pachyderma, G. bulloides and G. ruber within the surface sediments are on an average heavier by 27%, 34% and 40% respectively than shells of the same size within the plankton tows, indicative of secondary calcification. The planktic foraminiferal isotopes show the presence of heavier isotopes in the surface sediment foraminifera as compared to plankton tows, thus confirming secondary calcification. Secondary calcification in G. ruber occurs in the euphotic zone, whereas in case of N. pachyderma and G. builoides it is at deeper depths. We also observed a decrease in the shell spines in surface sediment foraminifera as compared to plankton tows, indicative of the morphological changes that foraminifera underwent during gametogenesis.

关键词： Southern Ocean foraminifera climate change stable isotopes shell weight

Shallow Marine Cenomanian-Turonian Benthic foraminifera and Kerogen Type from Mangoule, Logbadjeck Formation, Douala/Kribi-Campo Basin, Cameroon, West Africa

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Open Journal of Marine Science 2022年第3期12卷 108-125页

作者： Olivier Anoh Njoh Naomi Sama Yaya Sali Department of Geology Mining and Environmental Science Faculty of Science The University of Bamenda Bamenda Cameroon

An integrated benthic foraminiferal and organic matter analysis of samples obtained from sedimentary sections exposed in the Mangoule-Bonepoupa area, revealed a very shallow marine paleo-depositional environment for the sediments studied, with considerable influx of continental organic matter that were accumulated during the Cenomanian-Turonian age. With reference to the lithostratigraphic profile of the Douala/Kribi-Campo Basin, the age obtained reveals that the sedimentary sections studied belong particularly to the lower section of the Logbadjeck/Mungo River Formation, based on the following benthic foraminifera assemblage: Ammobaculites jessensis, Ammobaculites benuensis, Ammobaculites coprolithiformis, Ammotium cf nkalagum, Ammotium nwalum, Haplophragmoides cf beuchensis, Trochamina taylorana. A particularly very poor palynomorph assemblage was recovered and included no age diagnostic species: Acrostichum aureum, Lycopodiumsporites sp., Fungal spore, Lavigatosporites discordatus, Longapertites sp., Verrucosisporites sp. An organic petrographic analysis performed on these samples revealed Kerogen Type-II and Type-III. The entire data sets obtained from this area is remarkably poor and we suspect poor preservation as the cause viewing the extent of weathering. The paleo-depositional environment of these sediments was suggested both from the foraminifera and palynomorphs present and confirmed from the organic matter types and macrofossil contents. The studied sections are composed generally of dark to dark-gray shale beds. As one of the petroleum producing basins within the Gulf of Guinea in which exploration/exploitation activities are on-going, the current research is aim at providing more data useful in the continuous search for more potential source rocks in this basin.

关键词： Assemblage Cenomanian-Turonian foraminifera Kerogen-Type Palynomorphs Recovery

DISTRIBUTION OF ARENACEOUS foraminifera ALONG CHINA COAST AND ITS CONTROLLING FACTORS

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Chinese Science Bulletin 1989年第22期34卷 1896-1901页

作者：吴乃琴汪品先 Department of Marine Geology Tongji University Shanghai 200092 PRC

In recent years, foraminiferal faunas began to play an important role in the study of sea level change and coastal evolution in China. foraminifera are well known to have two groups in terms of the test composition: c... 详细信息

关键词： arenaceous foraminifera pH value coastal zone

The marine environmental evolution in the northern Norwegian Sea revealed by foraminifera during the last 60 ka

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Advances in Polar Science 2021年第3期32卷 210-220页

作者： WANG Weiguo ZHAO Mengwei YANG Jichao XIAO Wenshen WANG Haoyin LIU Yang Third Institute of Oceanography Ministry of Natural ResourcesP.R.C.Xiamen 361005China Pilot National Laboratory for Marine Science and Technology Qingdao 266237China Shandong University of Science and Technology Qingdao 266590China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China School of Marine Science and Technology Hainan Tropical Ocean UniversitySanya 572000China School of Earth Sciences Lanzhou UniversityLanzhou 730000China

Both planktonic and benthic foraminifera were identified in a sediment core collected from the northern Norwegian Sea to reconstruct the paleoceanographic evolution since the last *** assemblages and distribution patterns of dominant foraminiferal species with special habitat preferences indicated that three marine environments occurred in the northern Norwegian Sea since 62 ka BP:(1)an environment controlled by the circulation of the North Atlantic Current(NAC);(2)by polynya-related sinking of brines and upwelling of intermediate water surrounding the polynya;(3)by melt-water from Barents Sea Ice Sheet(BSIS).At 62-52.5 ka BP,a period with the highest summer insolation during the last glaciatial period,intensification of the NAC led to higher absolute abundances and higher diversity of foraminiferal *** higher abundance of benthic species Cibicidoides wuellerstorfi indicates bottom water conditions that were well-ventilated with an adequate food supply;however,higher abundances of polar planktonic foraminiferal species Neogloboquadrina pachyderma(sin.)indicate that the near-surface temperatures were still *** mid-late Marine Isotope Stage(MIS)3(52.5-29 ka BP),the marine environment of the northern Norwegian Sea alternately changed among the above mentioned three *** 29-17ka BP during the last glacial maximum,the dominant benthic species Bolivina arctica from the Arctic Ocean indicates an extreme cold bottom *** BSIS expanded to its maximum extent during this period,and vast polynya formed at the edge of the ice *** sinking of brines from the formation of sea ice in the polynyas caused upwelling,indicated by the upwelling adapted planktonic species Globigerinita *** 17-10 ka BP,the northern Norwegian Sea was controlled by *** the ablation of BSIS,massive amounts of melt water discharged into the Norwegian Sea,resulting in strong water column stratification,poor ventilation,and an oligotrophic

关键词： Norwegian Sea foraminifera North Atlantic Current Barents Sea Ice Sheet marine environments last glaciation

OXYGEN ISOTOPIC RECORD AND ITS PALEOCLIMATIC IMPLICATIONS OF BENTHONIC foraminifera OF EAST CHINA SEA CORE SHIM-I IN MID-EOCENE,PLIOCENE AND EARLY-PLEISTOCENE

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Chinese Science Bulletin 1990年第24期35卷 2076-2080页

作者：王大锐王乃文 S.G.WHITTAKER Scientific Research Institute of Petroleum Exploration & Development Beijing 100083 PRC Institute of Geological Sciences Chinese Academy of Geological Sciences Beijing 100037 PRC Department of Geological Sciences University of Saskatchewan Canada S7N OWO

Oxyegen and carbon isotopic ratios in the Quatermary-Pliocene,Pleistocene and Eocene Benthonic foraminiferahave been investigated from a single core drilled inthe East

关键词： foraminifera stable isotope paleotemperature.