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  1. Artikel: Microbiotas of the banded iron formations.

    Cloud, P E / Licari, G R

    Proceedings of the National Academy of Sciences of the United States of America

    2002  Band 61, Heft 3, Seite(n) 779–786

    Sprache Englisch
    Erscheinungsdatum 2002-09-13
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.61.3.779
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: A new chroococcacean alga from the proterozoic of queensland.

    Licari, G R / Cloud, P E / Smith, W D

    Proceedings of the National Academy of Sciences of the United States of America

    2002  Band 62, Heft 1, Seite(n) 56–62

    Abstract: Nannofossils section sign here described are from the middle Proterozoic Paradise Creek Formation, along Paradise Creek in northwestern Queensland, Australia. These fossils, in chert blebs associated with branched stromatolites, comprise cubic colonies ... ...

    Abstract Nannofossils section sign here described are from the middle Proterozoic Paradise Creek Formation, along Paradise Creek in northwestern Queensland, Australia. These fossils, in chert blebs associated with branched stromatolites, comprise cubic colonies analogous to living Eucapsis, a member of the blue-green algal family Chroococcaceae. The age of the enclosing rocks, bracketed by the ages of older and younger granitic events, is about 1.6 x 10(9) years. We record, therefore, a new chronological and biological datum in the currently accumulating sequence of pre-Paleozoic microbiotas.
    Sprache Englisch
    Erscheinungsdatum 2002-09-13
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.62.1.56
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel: Proterozoic eucaryotes from eastern california.

    Cloud, P E / Licari, G R / Wright, L A / Troxel, B W

    Proceedings of the National Academy of Sciences of the United States of America

    2002  Band 62, Heft 3, Seite(n) 623–630

    Abstract: Both procaryotic and eucaryotic nannofossils occur in chert from the upper Beck Spring Dolomite (Pahrump Group) in northeastern San Bernardino County, California. These fossils include the oldest reasonably certain records to date of chlorophycean and ... ...

    Abstract Both procaryotic and eucaryotic nannofossils occur in chert from the upper Beck Spring Dolomite (Pahrump Group) in northeastern San Bernardino County, California. These fossils include the oldest reasonably certain records to date of chlorophycean and chrysophycean algae, and hence of the eucaryotic or mitosing cell. Associated with these are cyanophycean procaryotes of still more ancient affinities. Indirect radiometric evidence implies an age of 1.2 to 1.4 aeons (1.2 to 1.4 x 10(9) years) for the enclosing rocks. Associated stromatolites are consistent with such an age assignment.
    Sprache Englisch
    Erscheinungsdatum 2002-09-13
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.62.3.623
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel: Prokaryotic algae associated with Australian proterozoic stromatolites.

    Licari, G R / Cloud, P

    Proceedings of the National Academy of Sciences of the United States of America

    1972  Band 69, Heft 9, Seite(n) 2500–2504

    Abstract: Five instances of association between distinctive stromatolites and blue-green algal nannofossils are recorded from a 100-m sequence of carbonate rocks about 1.6 x 10(9) years old, along the south side of Paradise Creek, northwestern Queensland, ... ...

    Abstract Five instances of association between distinctive stromatolites and blue-green algal nannofossils are recorded from a 100-m sequence of carbonate rocks about 1.6 x 10(9) years old, along the south side of Paradise Creek, northwestern Queensland, Australia. No eukaryotes were identified in any of these systematically limited assemblages, although they are known from rocks as old as 1.3 x 10(9) years in eastern California. Thus, eukaryotes may not have appeared until after 1.6 x 10(9) years ago (but before 1.3 x 10(9) years ago). The associations observed would also be consistent with (but do not prove) a biotic influence on stromatolite morphology. As is usual among prePaleozoic forms described, the morphology of the nannofossils is very similar to living forms, displaying marked evolutionary conservatism. Primary orientation of stromatolitic laminae and columns is not invariably convex upward, as conventionally believed, but convex away from and parallel to the initial point or surface of attachment, which may be horizontal or even downward beneath overhangs.
    Mesh-Begriff(e) Australia ; Biological Evolution ; Carbonates ; Cyanobacteria ; Geological Phenomena ; Geology ; Paleontology
    Chemische Substanzen Carbonates
    Sprache Englisch
    Erscheinungsdatum 1972-09
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.69.9.2500
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Artikel: Reproductive structures and taxonomic affinities of some nannofossils from the gunflint iron formation.

    Licari, G R / Cloud, P E

    Proceedings of the National Academy of Sciences of the United States of America

    1968  Band 59, Heft 4, Seite(n) 1053–1060

    Mesh-Begriff(e) Eukaryota/cytology ; Microscopy, Phase-Contrast ; Ontario ; Paleontology
    Sprache Englisch
    Erscheinungsdatum 1968-04
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.59.4.1053
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel: Micromorphology and surface characteristics of lunar dust and breccia.

    Cloud, P / Margolis, S V / Moorman, M / Barker, J M / Licari, G R / Krinsley, D / Barnes, V E

    Science (New York, N.Y.)

    1970  Band 167, Heft 3918, Seite(n) 776–778

    Abstract: Although nothing of direct biologic interest was observed in the sample studied, small shaped glass particles and glazed pits resemble objects which elsewhere have been described as fossils. These features, although nonbiological, do bear on processes of ...

    Abstract Although nothing of direct biologic interest was observed in the sample studied, small shaped glass particles and glazed pits resemble objects which elsewhere have been described as fossils. These features, although nonbiological, do bear on processes of lunar weathering and outgassing. The glazed pits are impact features. Fusion of their surfaces released gases. Electron microscopy of the glasses, pits, and angular microfractured mineral grains indicates a prevalence of destructive weathering processes-thermal expansion and contraction, abrasion by by-passing particles, and, of course, impact. ous at room temperature.
    Sprache Englisch
    Erscheinungsdatum 1970-01-30
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.167.3918.776
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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