[b-uley] gypsum deposits OF NEW BRUNSWICK L\ 7 



bedding or lamination. They seldom exceed an inch in diameter. No 

 fibrous gypsmn or satin spar occurs in the massive plaster rock, but 

 veins of this character, usually less than an inch in width, are found 

 in the associated red sandy and clayey beds, and are evidently of later 

 origin. In colour the rock varies from snowy whiteness to shades of 

 gray, blue and salmon red, being sometimes mottled, selenite crystals 

 when they occur being usually darker than the rock in which they 

 are imbedded. The red colour is most pronounced in the vicinity of 

 cracks or layers containing red clay, though sometimes diffused through 

 considerable masses. 



Chemical analysis of the first grades of the gypsum rock show it 

 to contain 99.88 per cent of hydrated sulphate of lime, with only traces 

 of iron, silica and magnesia, but in inferior grades there may be found 

 carbonate as well as sulphate of lime, with both silica and iron, though 

 m inconsiderable amounts. 



An important feature in any discussion of the gypsum deposits 

 of Albert county is that of their arrangement, to which must be added 

 the evidences which they afford of deformation. In many parts of the 

 quarries the indications of stratification or of lamination are very 

 marked, as illustrated in the accompanying plate (see Plate III), and 

 are sometimes made more evident by bands of small selenite crystals 

 arranged on either side of a bedding plane, or, in some instances, with 

 this plane bisecting individual crystals. The planes of lamination are 

 at times very regular, at others wavy or corrngated, and, though in 

 general not as a whole far from horizontal, occasionally exhibiting 

 inclination of 30° or more. The corrugations referred to and local 

 crumplings may in part be due to pressure resulting from hydration, 

 or from removal of support through the effects of solution, but the study 

 of the district as a whole, and especially of the relations of the gypsnm 

 beds to the underlying limestones, show that both of these rocks have 

 been subjected to deformation, determining a general synclinal structure, 

 the broad and open basin thus produced being partly divided into 

 smaller basins by low anticlinal domes. From the study of these 

 relations (see section) we are also led to the inference that the 

 original thickness of the plaster beds must have been at least 300 feet, 

 as also that over considerable areas this had been removed by denudation 

 prior to the commencement of quarrying operations. The effects of 

 the solvent action of waters are everywhere to be seen in the broken, 

 castellated or turreted aspect of the g3T)sum bluffs, in the abundance 

 of pot-holes, often, as already noted, crowdedly grouped, and in the 

 evidences of underground drainage. In addition to evidences of 

 plication the rocks show also the effects of lateral pressure in the pro- 



