so C. 71:3 



1854.] 



GEOLOGY OP WESTERN CANADA. 



73 



Cjje ^^HitiiHait laiirnaL 



TORONTO, NOVEMBER, 185 4. 



Geology of Western Canada.— No. IIL* 



[From the Report of Alex. Murray, Esq. Assistant Procincial 

 Geologist, dated Montreal, January, 1849.) 



WESTERN AND UURON DISTRICTS. 



Gypsiferous Limestone and Shale, and Corniferous Limestone. 



There are no hard rock exposures of any kind on the coa.st 

 south from the Riviere au Sable (north) for upwards of seven- 

 teen miles, or on the Sauguine River so far as we ascended it. 

 The first discovery of such strata in situ, on our route in that 

 direction, was at a point about seven miles nearly S. W. from 

 the mouth of the latter stream, where an outcrop occurs 

 displaying buff-coloured limestone, holding numerous organic 

 remains, of which the forms were frequently replaced by horn- 

 stone. The beds were in no case at this place exposed above 

 two feet over the level of the lake, and their approach to 

 horizontality was so near that the eye could scarcely detect a 

 slope. They came out at intervals along the shore, the sur- 

 face of one bed being sometimes exposed for a considerable 

 distance, and occupied altogether a space of four or five miles, 

 beyond which another concealment occurs, continuing to within 

 three miles of Point Douglas, where 3'ellowish coloured calca- 

 reous sandstone skirts the coast line. Proceeding along the 

 beach towards Point Douglas, we found this sandstone asso- 

 ciated with calcareous beds holding a large amount of horn- 

 stone, with black bituminous shales and blue and drab-coloured 

 limestones, one bed among which appeared to be hydraulic. 

 The whole of these strata were devoid of fossils, but imperfect 

 crystals of celestine or sulphate of strontian occurred, with 

 quartz and calc-spar, lining drusy cavities or cracks in the 

 rock, and numerous imbedded balls of horn.stone were met 

 with. A black band overlies the sandstone, and is of a coarse 

 granular texture, appearing to be composed principally of an 

 aggregation of imperfect crj'stals of calc-spar, while the black 

 color results from the presence of bituminous matter, which 

 exists in greater or less proportion in all the beds. Ascending 

 in the section, which at Point Douglas displays a thickness of 

 twelve feet, thin calcareous beds of a dark brown colour occur, 

 separated by very thin layers of black bituminous shale ; and 

 over them the upper part of the clift' is occupied by thin bands 

 of blue limestone and pale yellowish calcareous beds, some- 

 times over a foot in thickness, much marked by small brownish 

 lenticular crj-stals of calc-spar. Between two of the beds there 

 is a suture-like division ; the two beds when separated present 

 surfaces covered with inter-fitting tooth-like projections, the 



* In the August number of this Journal we published a Geological 

 Map of a consiilcrable portion of Western Canada, by W. E. Logan, 

 Esq., F.R.S. & G.S., Provincial Geologist. We now propose to fur- 

 nish monthly abstracts of those portions of the Geological Reports 

 which describe the physical structure of the country comprehended 

 within the limits of the Map. We are induced to adopt this method of 

 disseminating information respecting the Geology of Canada, not only 

 on account of its intrinsic value, but also because it is a matter of 

 extreme difficulty to meet with copies of the earlier Reports, in conse- 

 quence of the destruction of the reserve during tliose disastrous confla- 

 grations which destroyed the Parliament Buildings at Jlontrcal and 

 Quebec. 



Vol. in., No. 4, November, 1854. 



sides of which often display a fasiculated columnar struc- 

 ture, and a film of bituminous matter lies between the surfaces, 

 and invests all the projections. One part or another of the 

 non-fossiliferous section thus exposed at Point Douglas con- 

 tinues to occupy the coast to the southward, exhibiting gentle 

 undulations, to a spot about half a mile beyond the Little Pine 

 Brook, where fossiliferous beds, holding much hornstone, are 

 seen overlying the highest of the strata already mentioned, in 

 detatched isolated patches, for upwards of a mile, beyond 

 which no ledge is exposed for upwards of twenty-five miles. 



Where the line between the Townships of Ashfield and Col- 

 borne meets the lake, a little south of JIaitland River, ledges 

 come from beneath the high claj' cliffs which face the water, 

 and these ledges are seen at intervals along the shore for about 

 a mile. The greatest section exposed does not afibrd a vertical 

 thickness of more than six feet ; the rocks resemble a part of 

 those of Point Douglas ; they are destitute of fossils, and con- 

 sist, in ascending order, of gray calcareous and bituminous 

 sandstones, cherty limestones, brown calcareous beds striped 

 with thin bituminous .shales, and pale yellow calcareous layers, 

 sometimes three feet thick, with lenticular crystals of calc-spar, 

 or cavities from which such have disappeared. Probably in 

 the same relation to these rocks as the fossiliferous to the un- 

 fossiliferous of the vicinity of Point Douglas,_ there occur at 

 the falls on the Ashfield River, about a quarter of a mile 

 above the village, a set of thick-bedded dark gray calcareous 

 sandstones and buff-coloured silicious limestones, both holding 

 organic remains, which are more nuiuerous in the latter. 

 Beds similar to those on the Ashfield coast and river, pro- 

 babl}' a continuation of the same, were observed for the last 

 time in a cliff on the Maitland River near Goderich. The 

 following is a section of them in descending order : — 



ft. in. 



1. Thin-bedded dark gray bituminous limestone holding organic 

 remains ; a suture-like bituminous division with tooth-like 

 and occasionally columnar-sided projections, separate two of 



the beds 24 



2. Measures concealed by clay and debris 12 



3. Pale gray or drab-coloured fine grained sandstone, with fer- 

 ruginous spots and stripes and mottled with blue and yellow : 



no fossils 2 



4. An irregular bed composed of an agregation of imperfect 

 crystals of calc-spar 1 



5. Dai-k brown fine-grained sandstone striped with bituminous 

 layers, very soft and easily disintegrated >intil after exposure 



to the air, when it becomes hard '2 6 



At the bridge across the Maitland River, about half a mile 

 from the village of Goderich, and at a short distance below 

 the place where the above section was mca.sured, the following 

 unfossiliferous rocks were found exposed in a continuation of 

 the same cliff : — 



ft. in. 



2. Dark gray bituminous and silicious limestone 4 



Brecciatcd, cherty and bituminous limestone 2 



3. Pale yellowish calcareo-arcnaceous bed, with ferruginous 

 stripes and spots .1 10 



4. Bed composed of an aggregation of imperfect crirstals of 

 calc-spar 6 



5. Soft yellowish coloured sandstone ■with bituminous and fer- 

 ruginous spots 3 



C. Dark gray or brownish coloured bituminous limestone con- 

 taining small lenticular crystals of calc-spar or cavities of 

 the same form, some beds showing a large quantity of hoi-n- 

 stone and thin partings of black bituminous shale 4 



The lower and non-fossiliferous portion of the rocks thus 

 described bears a strong resemblance in their mineral character 



