摘要:

AbstractThe amino acid signature of fourteen genera of Mollusca, both Bivalvia and Gastropoda, was determined on over 300 individual valves. Examination of eight specific sets of amino acid ratios (for example: aspartic acid/glutamic acid, leucine/valine) indicates that these 14 genera (Patella, Littorina, Nucella, Buccinum, Turritella, Macoma, Scrobicularia, Mytilus, Cerastoderma, Arctica, Gtycymeris, Venus, Mya, andHiatelld) can be distinguished one from another with a high degree of certainty.Discrimination between genera can be based on quantitative assessment of the probability of an individual analysis belonging to a specific genus. We conclude that the amino acid signature is sufficiently distinct that small shell fragments can be assigned to a genus on the basis of the amino acid chromatography. In some instances, for exampleLittorina, it may even be possible to identify fragments to specific species.

ISSN:0072-1050    

DOI:10.1002/gj.3350200102

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractCoronates form a small but distinctive group of lower Palaeozoic echinoderms, most closely related to eublastoids. The coronate fauna of Czechoslovakia includesMespilocystites bohemicusBarrande 1887 from the Lower and Middle Caradoc, characterized by a conical theca, coronal processes which diverge markedly upwards, and distinctly angled radial furrows;Stephanoblaslus mints(Barrande 1887), from the Wenlock, typified by an elongate bud‐shaped theca with three radiating keels at the base and a very narrow stem; and‘Stephanocrinus’ gemmiformis(Hall 1852) from the Ludlow, with a cup‐shaped theca and low coronal processes.‘S.’ gemmiformishas not previously been reported from outside North America or above

ISSN:0072-1050    

DOI:10.1002/gj.3350200103

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractBiostratigraphy and lithostratigraphy of some exposures of upper Ludlow and lower Downton rocks near Kington, Herefordshire are described in detail. Temporary exposures created during the construction of the new Kington by‐pass are particularly informative. One small exposure of Lower Whitcliffe Formation is recorded. The Upper Whitcliffe Formation is well displayed in characteristically fossiliferous shelly siltstones. The Downton succession begins with the Ludlow Bone Bed Member. This and the succeeding Platyschisma Shale Member complete the local development of the Downton Castle Sandstone Formatio

ISSN:0072-1050    

DOI:10.1002/gj.3350200104

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractThe arcuate pattern of the main Caledonian cleavage and associated fold axial plane traces in North Wales is due partly to NW‐SE compression with tectonic transport to the southeast against the concealed crop of the Tan y grisiau Microgranite. Low‐angle cleavage close to the microgranite is shown to be a local variant of the regional cleavage formed during the main deformation and not an earlier phase as previously supposed. Transcurrent movements along several major fault systems are also related to compression around the microgranite and the Harlech Dome bl

ISSN:0072-1050    

DOI:10.1002/gj.3350200105

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractThe arcuate Broadford anticline of south‐central Skye folds a sequence of strata ranging in age from late Precambrian to Jurassic. The Ordovician carbonate rocks of the core of the anticline are strongly extended parallel to bedding and deformation at some localities reaches up into unconformable Mesozoic strata. Three classes of Tertiary minor intrusion are recognized in the deformed sediments. The younger two are post‐kinematic. The effect of deformation on discordant sheets of the oldest class is obvious, as they are folded. It now seems, however, that the boudins previously reported (Nicholson 1970; Longman and Coward 1979) are sections through finger‐like igneous bodies (Farmin 1941; Pollardet al.1975). Stiff in relation to the carbonate country rock, the latter retained igneous textures and chilled margins when deformed. Deformation probably took place as the main period of plateau‐lava eruption ended and the succeeding phase of shield volcanoes and major intrusive centres began. As deformation is restricted to the core of an arcuate fold forming part of a volcanic complex, it may speculatively be suggested that the deformed rocks lie above an arcuate diapir, formed in an acid magma body subjected to volcan

ISSN:0072-1050    

DOI:10.1002/gj.3350200106

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350200114

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350200109

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350200111

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350200112

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350200113

出版商:John Wiley&Sons Ltd    

年代:1985

数据来源: WILEY