Annual report . rentian and Huronian systems were first examined in some detail.* In that yearLogan met with and accurately described, severally, rocks which we now refer to (1)The Fundamental Gneiss; (2) The Grenville Series; and (3) The Huronian. He speaksof the rocks of the first class as being in the main syenitic gneisses of a highly crystal-line quality, belonging to the order which, in the nomenclature of Lyell, is called nieta-morphic instead of primary, as possessing an aspect inducing a theoretic belief that theymay be ancient sedimentary formations in an altered condition. In what w
Annual report . rentian and Huronian systems were first examined in some detail.* In that yearLogan met with and accurately described, severally, rocks which we now refer to (1)The Fundamental Gneiss; (2) The Grenville Series; and (3) The Huronian. He speaksof the rocks of the first class as being in the main syenitic gneisses of a highly crystal-line quality, belonging to the order which, in the nomenclature of Lyell, is called nieta-morphic instead of primary, as possessing an aspect inducing a theoretic belief that theymay be ancient sedimentary formations in an altered condition. In what we now callthe Grenville Series, he describf s the association of crystalline limestones and inter-bedded gneisses, adding that it appeared to be expedient to consider this mass as aseparate metamorphic group, supposed to be newer than the last. Of the Huronian. therelations were at that time left undetermined, although it is observed that its beds holdpebbles of the underlying rocks, here the Fundamental Hcno (i. Vennor, (1N40-1NN4). Mr. Vennor was a member of the staff of the Geological Snrvej of the Province of Canada Ontarioand Quebec) from 18o to 1867, and of that of the Dominion of Canada from 1867 to his work was in connection with the pre-Cambrian rocks of southeastern Ontario and the adjacent i>;irtof Quebec. The picture is from a photograph taken about L876. In the Report for 1852-53 i published 1854), the name Laurentian was adopted forwhat bad been previously designated merely as tin- metanxorphic aeries. and in thegeological sketch printed in Paris in connection with the Exhibition oi 1855 (whichfollows next in order of publication), this system is stated to consist almost exclusivelyof much altered and disturbed sedimentary beds. It is also, however, made to includesome recognized Intrusives, such as granite and syenites, forming parts of the mass, aswell as the Labradorite rocks, which were afterwards lor a time named Upper Laurentian,an
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectminesandmineralresou
