The rocks of the two map-areas include paragneisses and acidic and basic intrusives. More than three-quarters of the rocks are of igneous origin; granitic types predominate. In the Nipissis River area granitic rocks are found west and north of the Nipissis and Nipisso Rivers, whereas basic intrusives are found east and south of the two rivers. A narrow band of paragneisses and migmatites separates the two main rock groups. Granitic rocks occupy the southern third, except for the southeast corner, and most of the northern quarter of the Nipisso Lake area.

This thesis is a petrographic study of the Intermediate Siltstone, an important sedimentary member at the Sullivan mine, Kimberley, British Columbia. In the thesis a study was made of the quartz eyes which occur at the base of the Intermediate Siltstone to determine their lateral distribution, their possible origin, and whether or not they have preferred optic orientation. The Sullivan mine Is on the south slope of Sullivan Hill, 1.5 miles north-west of the town of Kimberley in southeastern British Columbia, and 50 miles north of the International Boundary.

During the field season of 1952, the writer was employed on a geological survey party of the Ontario Department of Mines. The area examined is located in the Lumby lake greenstone belt, District of Kenora, Ontario, and the work was under the direction of R. S. Woolverton (1953) who has presented a doctoral dissertation of the geology of the area. During the course of the fieldwork many problems concerning the genesis of the rocks were encountered. Woolverton has dealt with some of them in his dissertation.

Quartz suitable for glass-making and as a source of silica for other industrial uses is being mined at St. Donat, Quebec, (frontispiece) by Dominion Silica Corporation. The writer undertook a field and laboratory study of the quartz deposits and surrounding rocks, the results of which are set forth below. The following problems were studied in detail; 1.the rocks present, their composition, distribution, and structure, 2. the genesis of the quartz deposit, 3• the source of the associated kaolin.

The northern flank of the Gaspesian extension of the Appalachian Mountain System is dominated by a belt of hills 2 to 12 miles in width which begins some 15 miles east of Lake Matapedia and extends 65 miles northeastward to end with the Tabletop mountains. This high belt, known as the Shickshock mountains, forms a physiographic but not geological unit, its eastern end being composed of intrusive granite and serpentine bodies whereas, to the west, over some two-thirds of its length, the peaks are the dissected remnants of a great block of Lower Paleozoic metavolcanic and associated metasedimentary rocks.

An investigation was made of chemical variation within garnet, chlorite, and plagioclase in the metamorphosed Standing Pond amphibolite of the Hanover quadrangle, New Hampshire-Vermont. The mineral assemblages epidoteplagioclase, sphene-rutile, ilmenite-rutile, garnet-rutile- ilmenite, and kyanite-muscovite are also discussed. Little correlation was round between metamorphic zone, ironmagnesium ratios and calcium and manganese content of the various minerals. The theoretical grounds for such correlation are discussed, and it is concluded that the apparent metamorphic grade fluctuates within zones because of minor differences in temperature-pressure conditions and bulk composition.

The primary object of the present work was to continue the experiments on beats of solution started by Moore (1955) in the Department of Geological Sciences, McGill University. In his work, Moore accumulated a fund of technical knowledge concerned with twin calorimeter construction and technique. He constructed twin calorimeters to determine the beats of solution of finely ground quartz crystal and quartz glass. He attempted to measure the surface and strain energy of these minerals but failed because he employed a quenching technique with the coarser fractions in order to reduce the length of the solution period.

Note: Missing Page 159. / In the summer of 1950 the writer, as an officer of the Geological Survey or Canada, was attached to the Baffin Expedition of the Arctic Institute of North America (A.I.N.A.). An area in east-central Baffin Island between latitudes 69°30' and 71° and longitudes 68° and 72° was covered by reconnaissance geological mapping in the course of the field season. The results of exploration of this geologically unknown area are presented in this dissertation.

In southern Quebec the Lower Ordovician or Beekmantown series consists of a thick sequence of dolomite beds with minor amounts of sandstone, limestone and shale. By comparison with Lower Ordovician strata elsewhere, the Beekmantown in southern Quebec is relatively unfossiliferous. As a result, interest in the group has been slight. This study is a dissertation on the stratigraphy and palaeontology of the Beekmantown group as exposed in the Quebec portion of the St. Lawrence Lowlands.

This paper is mainly concerned with the description and illustration of ostracod species collected from Ordovician sediments of the St. Lawrence Lowlands, the determination of their stratigraphic ranges, and the methods used in preparing the specimens for examination, identification and photography. A brief outline of the stratigraphy, structure and economics of these Ordovician sediments is included to provide a background for the palaeontological portion of the paper. [...]