lithostratigraphy and provenance of the neoarchean mckellar harbour sequence, superior province, ontario, canada
abstract
the mckellar harbour sequence is located on the shore of lake superior approximately
40 km west of the town of marathon, ontario. the sequence was examined in detail
through stratigraphic and geochemical investigations in order to determine the depositional
environment and provenance of these rocks.
four subsequences were identified in the mckellar harbour sequence, consistent with the
facies associated with a distal submarine ramp environment. the sequence shows
thickening and coarsening upward trends, indicative of progradation of the ramp onto the
basin floor. this indicates that the rocks of the mckellar harbour sequence are the distal
equivalents of the proximal submarine ramp facies identified in the beardmore-geraldton
and quetico terranes to the north of the study area. sedimentary strata from other potential
source regions did not exhibit the characteristic features of a submarine ramp, and were
likely deposited through different processes. insufficient data were collected to determine
the depositional environment for these units.
geochemical analyses indicate that the rocks of the mckellar harbour sequence have
immobile element chemistry that is very similar to that of the beardmore-geraldton and
quetico terranes, and that a continuum of deposition from north to south is present.
sediments generated in the beardmore-geraldton terrane were transported to small basins
associated with the schreiber-hemlo volcanic island system by a submarine ramp.
collections
- retrospective theses [1604]