306 WYNNE : GEOLOGY OP KT.ITCH. [PAET II. 



Vitonia Hill is an isolated peak, some 350 feet in height^ near 

 the south-western extremity of the large in- 



Vitonia peak. . , . 



trusion abovementioned. It is formed of intru- 

 sive, compact and sub-crystalline^ dark, columnar basalt, which strongly 

 affects the magnetic needle, crossed obliquely by a large irregular mass 

 of soft trap breccia, with a sub-stratified appearance inclined at 15° to 

 east-by-north. This is very friable and much decomposed^ its soft 

 debris slipping down the steep hill sides, but it contains cores or lumps 

 of harder trap. 



Some other intrusions of dark-grey trap occur in the vicinity, and 

 one dyke of the purple kind intersects strong white and thinner red 

 sandstones, coinciding with a line of reef or silicious fault rock east- 

 ward of Vitonia Hill. 



The plains of the neighbouring country are thickly covered by 

 sand, the smaller hills being generally trappean 



Plains. 



intrusions. 

 South-west of Vitonia a broad promontory-like escarpment of the 

 upper Jurassic rocks leaves the trap boundary, with 



Escarpment. ■ ■ ^ ■ , .i 



which it usually coincides, and projects north- 

 eastward into the plains. This escarpment was probably once covered 

 entirely by the traps, considerable outliers of which still remain eap- 

 pino- the hills of Lakria, Aklia, and some others in their vicinity, while 

 hilly o'round to the southward is entirely covered by their thick flows of 

 the usual character, alternating with some dark-colored powdery varieties 

 very similar to the soft band which crosses Vitonia Hill. 



If these were not originally deposited as volcanic ash, they seem 

 to have suffered from unusually intense decomposi- 



ow ery raps. ^_^^^ ^^^ general dip of the traps here is to 



the south-by-west, and the ground is crossed by a small, but distinct 

 scarp along the outcrop of some harder beds. 



( 206 ) 



