1849.] HAMILTON ON THE GEOLOGY OF ASIA MINOR. 365 



2. On the Geology of part of Asia Minor (Cappadoeia, &c.), by- 

 Mr. Hamilton. Vol. v. p. 583. 



3. On the Geology of the Western part of Asia Minor, by Messrs. 

 Hamilton and Strickland. Vol. vi. p. 1. 



Respecting that portion of iVsia Minor now more immediately under 

 consideration, I must also refer to a paper by Mr. Ainsworth on Asia 

 Minor in the Journal of the Royal Geographical Society, vol. ix. 

 p. 267 et seq. 



No idea can be formed of the general features and character of this 

 country, \\dthout taking into consideration the extent and variety of 

 igneous rocks by which it is everywhere penetrated and disturbed. 

 These are of every possible variety — granite of various qualities, green- 

 stones, domites, trachytes and trachytic conglomerates, like those de- 

 scribed in my former paper on the Geology of Cappadoeia. One 

 distinctive feature however is, that the remarkable volcanic tuffs and 

 peperites, so abundant between Mount Argaeus and Hassan Dagh, do 

 not occur so frequently in this part of Asia Minor, from which we may, 

 I think, conclude that it is of an older date. 



The hne of country to which my present remarks apply extends 

 from Tocat (lat. 36° 50' E.) to Sevrihissar (lat. 31° 35' E.), and in a 

 general direction from E.N.E. to W.S.W. 280 miles ; its extent from 

 N. to S. is irregular. The principal igneous rocks which I observed 

 in this district are granite, greenstone, porphyritic trap, serpentine, 

 trachyte and trachytic conglomerates, domite, basalt, and black vol- 

 canic tuff and peperite ; and I propose briefly stating the chief loca- 

 lities where these different rocks came under my notice. 



1. Granite^. — An elevated ridge of fine-grained grey granite, 

 sending out ramifications in several directions, surrounds the town of 

 Sevrihissar in a semicircular or elliptical form. At the eastern ex- 

 tremity of the igneous region about Angora, the red sandstone beds 

 repose against a mass of a dark granitic or rather syenitic rock. 



2. Greenstone and green trappean rocks. — It is difficult to draw 

 any precise line with regard to the distinctive characters of these 

 rocks, passing as they do in this district by such gradual changes into 

 so many various forms. Generally speaking, rocks of this character 

 occur in the promontory of Sinope ; in the castle hill of Boiavad ; 

 in the centre of the mountain range between Sinope and Boiavad ; 

 in the valley of the Iris six miles east of Tocat ; near the village of 

 Boyeuk ten miles east of Barsek Dere, and in the deep and precipitous 

 gorge of Barsek Dere itself. 



3. Porphyritic trap. — By this term I propose to designate those 

 igneous rocks which consist of small crystalline masses set in a homo- 

 geneous matrix of a darker colour. They occur a few miles west of 

 Amasia, between Ladik and Sonnisa ; in the valley of the Lycus below 

 Niksar, and in the vicinity of Angora, forming the base of the rocky 

 cliffs through a narrow gorge of which the stream of Angora flows ; 

 also a few miles east of Angora, apparently gradually passing into the 

 granitic rock described above, in the deep ravine of Barsek Dere. 



* From the general abundance of hornblende this rock frequently passes into 

 syenite in this district. 



2 c 2 



