Geology of the northern Lewis Hills, western Newfoundland
Jeffrey Alan Karson 1977
A dissertation submitted to the State University of New York at Albany in partial fulfillment of the requirements for the degree of Doctor of Philosophy
College of Arts and Sciences, Department of Geological Sciences
Advisors: J.F. Dewey and W.S.F. Kidd

ABSTRACT
The Lewis Hills is the southernmost of the four Bay of Islands Ophiolite Complex massifs. These massifs are considered to be the dissected remnants of a once nearly continuous thrust slice of oceanic crust and upper mantle of Early Ordovician age. The Lewis Hills Massif may be divided into three north south trending zones. The eastern zone (Bay of Islands Complex) is composed of variably deformed and recrystallized gabbro, troctolite, wehrlite and dunite cumulates and harzburgite tectonites. The western zone (Little Port Assemblage) consists of greenschist facies metagabbros, diabase dikes and minor quartz-diorite bodies. The central zone (Mount Barren Assemblage) is a 3 kilometer wide zone of highly deformed metagabbros and amphibolites cut by syn- and post- kinematic mafic and ultramafic intrusive bodies. The central zone grades into the western zone but has a sharp igneous contact against the eastern zone, it is proposed that the central zone rocks represent the deep crustal levels of an oceanic fracture zone preserved between two less deformed assemblages of oceanic crust and upper mantle. Along strike to the northeast, rocks similar to those of the eastern and western zones of the Lewis Hills are exposed in the Bay of Islands Ophiolite Complex and the Coastal Complex respectively. The Mount Barren Assemblage has not been previously described as part of the Coastal Complex and provides an important link between the Bay of Islands and Coastal Complexes. Detailed studies in the Lewis Hills permit fairly well constrained models to be constructed for the kinematics and timing of processes during the evolution of oceanic fracture zones and the obduction of the Bay of Islands Complex.

Karson, J.A., 1977. Geology of the northern Lewis Hills, western Newfoundland.
Unpublished PhD dissertation, State University of New York at Albany. 474pp., +xxii; 5 folded plates (maps)
University at Albany Science Library call number:  SCIENCE MIC Film QE 199 K37X
Copies of this PhD dissertation can be ordered from Proquest UMI

        Front matter (title, table of contents, abstract, acknowledgements) - 1.1MB pdf file
        Photo pages in dissertation (colour and greyscale photos with captions): - 32.6MB pdf file

    Plate 1a - Geology of the northern Lewis Hills, western Newfoundland (coloured geological outcrop map, scale ~1:14,800) 26.2MB pdf file
    Plate 1b - Geology of the southern Lewis Hills, western Newfoundland (coloured geological outcrop map, scale ~1:15,840) 14.4MB pdf file
    Plate 1x - map legend from plate 1a  4.4MB pdf file
    Plate 2 - Structural map of shear zones in the northern Lewis Hills, western Newfoundland (part coloured geological map, scale ~1:14,800) 22.8MB pdf file
    Plate 3 - Structural map of lineations and fold axes in the northern Lewis Hills, western Newfoundland (uncoloured geological map, scale ~1:14,800) 6MB pdf file
    Plate 4 - Structural cross sections of the northern Lewis Hills, western Newfoundland (coloured geological sections, scale ~1:14,800) 13.8MB pdf file
    Plate 5 - Compressional velocities of mafic and ultramafic rocks in the northern Lewis Hills, western Newfoundland
                    (uncoloured geological map with overlay diagrams, scale ~1:14,800) 5.7MB pdf file
    Table 14 - Relative chronology of geological events in the northern Lewis Hills
    Fig 6.2 - Geological overview map of the northwestern Lewis Hills

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