Notes on the Geology of Bray Head. 333 



DESCRIPTION OF THE PLATES. 



Plate XXIY. 



A. — The northern exposure of the tipper quartz reef. 



A'. — Supposed detached portion of the northern exposure of the upper 

 quartz reef 



B B'. — Northern exposure of the lower quartz reef in places broken up 

 aud displaced by transverse faults. 



C D E. — Supposed outcrop of the main fault (Brandy Hole fault), a 

 down-throw to the south, which brings down the quartz reefs, tlaus 

 causing them again to appear at the surface further to the sotithward. 



D. — Line of outcrop along the general strike of the strata, marked 

 by a hollow filled with drift and peaty accu.mulations. 



D E. — Line of outcrop along the principal breaks that cross the strata, 

 marked by steep and abrupt ground south-west of this line. 



E C. — Probable line of strike of the main fault. 



D D'. — The southern exposure of the upper quartz reef A due to the 

 southward down-throw of the main fault. The reef is much broken 

 up and displaced by transverse faults. 



D". — Detached portions of the Ballynamuddagh quartz reef, whose re- 

 lations to the reef D D' are obscure. 



E, — The southern exposure of the lower quartz reef B B' due to the 

 southerly down-throw of the main fault. The reef is broken and 

 displaced by transverse faults. 



Plate XXY. 



Section along the coast line from South to North. In this section 

 the upper quartz reef is not seen, while the south and north exposures 

 of the lower quartz reef appear respectively at E and B. 



Plate XXVL . 



Pig. 1. — Section of the northern portion (B) of the lower quartz reef, 

 as seen on the west side of the railway cutting. 



Fig. 2. — Plan of the northern portion (B) of the lower quartz reef, 

 between the railway and the coast line. The quartz to the south-east 

 has been removed along a large joint, so as to expose the tinderlying 

 slates and grits on the shore. 



Fig. 3. — Sketch section of the rocks along the west side of the railway 

 cutting at Bray Head, illustrating the manner in which the rocks are 

 twisted, broken, and displaced by the numerous fault lines — line a h 

 indicates the site of the cliff path. 



Fig. 4. — Plan of the rocks between the railway and coast line at 

 Bray Head. 



SciEsr. Pkoc. R.D.S. Vol. hi., Pt. vi. 9 D 



