80 
plateau, having for the greater part of the area a southeasterly 
dip of 5°—10°. It is overlain on the east and southeast by two 
considerable patches of melaphyr, detached areas of what must 
originally have been a continuous flow. This melaphyr is a 
greenish to purplish, compact or finely crystalline, non-amygda- 
loidal variety, containing epidote in minute crystallizations and 
also larger segregations of both epidote and red jasper. It is 
distinctly different from, and undoubtedly older than, any mel- 
aphyr in the Central or Coastal areas, although bearing some 
resemblance to the more basic porphyrites. 
The contact between the basal conglomerate and the south- 
eastern patch of melaphyr is very clearly exposed, especially on 
the west side of the melaphyr, and the melaphyr unquestionably 
overlies the conglomerate. The contact appears on the map as 
a regular curve convex to the northwest, indicating that the 
melaphyr lies in a shallow trough. This appearance is due 
partly, however, to the very plain east-west fault which marks 
the northern edge of the melaphyr, with a downthrow to the 
south of, perhaps, ten feet. The melaphyr is distinctly and 
comformably overlain on the southeast by two small patches of 
what must be a second bed of conglomerate, since the melaphyr 
separates it from the basal conglomerate. These outlines owe 
their preservation chiefly to the two east-west faults shown on 
the map and downthrowing to the south ten and fifteen feet, 
approximately. The boundary fault separating these rocks 
from Granite Plateau is an absolute necessity at this point ; for 
their nearly level beds are vis-a-vis with the abrupt ledges of 
granite. "Phe displacement here cannot be less than twenty- 
five nor, probably, more than fifty feet; for the basal conglom- 
erate, which eaps the granite on the south side of the fault, is 
at least forty and possibly fifty feet thick, and the overlying 
melaphyr is twenty-five to thirty feet. 
The northern area of melaphyr appears also to occupy a 
shallow trough, and the intervening portion of the basal con- 
glomerate must be slightly anticlinal in structure ; although the 
ridge coinciding with dikes 22 and 34, and slightly capped with 
