PROCEEDINGS 



OF 



THE GEOLOGICAL SOCIETY OF LONDON. 



Vol. II. 1838. No. 54. 



January 17, — A paper by Dr. Bell, entitled "Geological Notes 

 to accompany Major Todd's Sketch of part of Mazunderan," was 

 first read. 



These notes were made during a journey from Teheran (lat. 35" 

 40' N., long. 50° 52' E.), eastward to Feeroozkooh, then northward 

 across the Elboorz mountains, and afterwards along the course of the 

 river Talar to the Caspian, and back to Teheran by the banks of the 

 river Heraz. The author's observations are given in the order in 

 which they were made during his journey, but the geological details 

 may be classed as follows : — 



1. Alluvium. — Teheran stands on a plain, consisting chiefly of the 

 debris of limestone and trap rocks. In the bed of a river at the 

 Caravanserai of Dalee Chaee, about 62 miles direct E. from Te- 

 heran, is a loose conglomerate composed of fragments of limestone 

 and trap, imbedded in dried mud. A similar deposit forms low hills 

 and valleys in several other places along the line of route, followed 

 by the author, as at the river Gazan Chaee, and on the summits of the 

 hills bordering the plain of Feeroozkooh. Below Pul-i-Seffeed, on 

 the Talar, is a conglomerate, formed of debris from the neighbour- 

 ing mountains, united by a calcareous cement. Further down the 

 river, it is finer, and stated to contain minute fragments of shells. 



Below Sheergah, the country, as far as the Caspian, is an alluvial, 

 muddy flat. This sea is stated to be fast filling up, and the disco- 

 loured water of the streams, which flow into it, may be traced for 

 five or six miles. Near the shore the water is so fresh that horses 

 drink it ; and Dr. Bell says, that the shells are chiefly freshwater. 

 Half imbedded in the banks of mud and sand are innumerable trunks 

 of large trees which have been drifted down by the rivers. A con- 

 glomerate similar to that at Dalee Chaee, was noticed at Karoo in 

 ascending the Herza ; also below the small stream Abi Noor, at the 

 foot of Demavend Peak. 



Lithographic Limestone. — A fine-grained limestone, used for litho- 

 graphy in Teheran, forms a high ridge north of the city, the beds 

 dippmg to the north, and resting on serpentine, porphyritic claystone, 

 and porcelain stone. In connexion with a blue limestone, it extends 

 over an immense tract to the N. and N.W. of Teheran, on the 



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