• Login
    View Item 
    •   Home
    • Brock Theses
    • Masters Theses
    • M.Sc. Earth Sciences
    • View Item
    •   Home
    • Brock Theses
    • Masters Theses
    • M.Sc. Earth Sciences
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of BrockUCommunitiesPublication DateAuthorsTitlesSubjectsThis CollectionPublication DateAuthorsTitlesSubjectsProfilesView

    My Account

    LoginRegister

    Statistics

    Display statistics

    Structural, stratigraphic and geochemical studies of the Horwood Peninsula - Gander Bay Area, Northeast Newfoundland /

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Brock_Wu_Tsai-Way_1979.pdf
    Size:
    8.910Mb
    Format:
    PDF
    Download
    Thumbnail
    Name:
    Wu fig.5.pdf
    Size:
    190.1Kb
    Format:
    PDF
    Download
    Thumbnail
    Name:
    Wu fig 4 A.pdf
    Size:
    468.6Kb
    Format:
    PDF
    Download
    Thumbnail
    Name:
    Wu fig 4 B.pdf
    Size:
    584.1Kb
    Format:
    PDF
    Download
    Thumbnail
    Name:
    Wu sections.pdf
    Size:
    139.2Kb
    Format:
    PDF
    Download
    View more filesView fewer files
    Author
    Wu, Tsai-Way.
    Keyword
    Geology, Structural.
    Geology, Stratigraphic.
    Geochemistry.
    Geology
    Geology
    
    Metadata
    Show full item record
    URI
    http://hdl.handle.net/10464/1641
    Abstract
    The Horwood Peninsula - Gander Bay area is located at NE Newfoundland in the Botwood Zone (Williams et a1., 1974) or in the Dunnage Zone (Williams, 1979) of the Central Mobile Belt of the Newfoundland Appalachians. The area is underlain by Middle Ordovician to possible Lower Silurian rocks of the Davidsville and Indian Islands Groups, respectively. Three conformable formations named informally : the Mafic Volcanic Formation, the Greywacke and Siltstone Formation and the Black Slate Formation, have been recognized in the Davidsville Group. The Greywacke and the Black Slate Formations pass locally into a Melange Formation. From consideration of regional structure and abundant locally-derived mafic volcanic olisto- 1iths in the melange, it is considered to have originated by gravity sliding rather than thrusting. Four formations have been recognized in the Indian Islands Group. They mainly contain silty slate and phyllite, grey cherty siltstone, green to red micaceous siltstone and limestone horizons. Repetition of lithological units by F1 folding are well-demonstrated in one of formations in this Group. The major structure in this Group on the Horwood Peninsula is interpreted to be a synclinal complex. The lithology of this Group is different from the Botwood Group to the west and is probably Late Ordovician and/or Early Silurian in age. The effects of soft-sediment deformation can be seen from the lower part of the Davidsville Group to the middle part of the Indian Islands Group indicating continuous and/or episodic slumping and sliding activities throughout the whole area. However, no siginificant depOSitional and tectonic break that could be assigned to the Taconian Orogeny has been recognized in this study. Three periods of tectonic deformation were produced by the Acadian Orogeny. Double boudinage in thin dikes indicates a southeast-northwest sub-horizontal compression and main northeast-southwest sub-horizontal extension during the D1 deformation. A penetrative, axial planar slaty cleavage (Sl) and tight to isocJ.ina1 F1 folds are products of this deformation. The D2 and D3 deformations formed S2 and S3 fabrics associated with crenulations and kink bands which are well-shown in the slates and phyllites of the Indian Islands Group. The D2 and D3 deformations are the products of vertical and northeast-southwest horizontal shortening respectively. The inferred fault between the Ordovician slates (Davidsville Group) and the siltstones (Indian Islands Group) suggested by Williams (1963, 1964b, 1972, 1978) is absent. Formations can be followed without displacement across this inferred fault. Chemically, the pillow lavas, mafic agglomerates, tuff beds and diabase dikes are subdivided into three rock suites : (a) basaltic komatiite (Beaver Cove Assemblage), (b) tholeiitic basalt (diabase dikes), (c) alkaline basalt (Shoal Bay Assemblage). The high Ti02 , MgO, Ni contents and bimodal characteristic of the basaltic komatiite in the area are comparable to the Svartenhuk Peninsula at Baffin Bay and are interpreted to be the result of an abortive volcano-tectonic rift-zone in a rear-arc basin. Modal and chemical analyses of greywackes and siltstones show the trend of maturity of these rocks increasing from poorly sorted Ordovician greywackes to fairly well-sorted Silurian siltstones. Rock fragments in greywackes indicate source areas consisting of plagiogranite, low grade metamorphic rocks and ultramafic rocks. Rare sedimentary structures in both Groups indicate a southeasterly provenance. Trace element analyses of greywackes also reveal a possible island-arc affinity.
    Collections
    M.Sc. Earth Sciences

    entitlement

     
    DSpace software (copyright © 2002 - 2022)  DuraSpace
    Quick Guide | Contact Us
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.