GEOLOGICAL ROUTE THROUGH ASIA MINOR 67 



very brilliantly colored in red and yellow, and rarely obscured by 

 plant cover, so that their bedding can be traced for long distances. 

 No unconformities were noticed, but the point of transition between 

 the shales immediately about Hammam and the calcareous con- 

 glomerates and sandstones to the north was not seen. As reported 

 by Tchihatcheff these deposits must be very extensive to the 

 north of our route; in fact they and others similar dominate the 

 formations of central Asia Minor. 



A gorge about an hour north of Hammam, near the village of 

 Arif, passes through a mass of much denser limestone, which 

 seemed to be conformable to the other deposits, but was very 

 different in appearance. It is indicated by heavier hatching on 

 the large map. 



Giaour Kalesi is close to the boundary between the series of 

 sandstones just described and one of the great plains that make 

 the type-landscape of central Anatolia. The boundary runs north- 

 east and southwest, and was followed most of the way from Ham- 

 mam Merkes to the Hohan Gol. The castle itself, however, is 

 on a pinnacle of very different rock, more similar to those which 

 wall the gorge at Arif and also to those at Angora and Assi Yuz- 

 gad. It may then be of the same period as the surrounding rock, 

 or with the Angora series, much older. There was no noticeable 

 continuation of it through the surrounding rolling country. All 

 the apparently earlier walls of- the castle were built of it. The 

 stones were small and yet show no great signs of weathering, in 

 marked contrast to the condition of Boghaz Koi, also built of its 

 local marble during the same period of history. Less than an hour 

 east of Giaour Kalesi is the village of Oyaja, built about the base 

 of two trap necks, like' a miniature Angora. These, or other 

 similar outcrops, furnished the material for the later heaviest 

 walls of Giaour Kalesi. 



Looking off from the top of Giaour Kalesi the hills seemed 

 spotted with deep green, the characteristic mark a little farther 

 east of the serpentines, and here doubtless due to the same cause. 

 The spots seemed to have no regular arrangement and perhaps 

 marked small volcanic necks, which, being soft, did not project 

 above the general level. 



