MEMOIRS 



OF 



THE GEOLOGICAL SURVEY OF INDIA 



The Geology of Idar State. By C. S. Middlemiss, 

 C.I.E., F.G.S., Late Superintendent, Geological Survey 

 of India. 



INTRODUCTION. 



Idar State is the principal Rajput State of the Mahi Kantha 

 Agency in the Bombay Presidency, having an 

 Political and I'hysi- £ ^ «gg square miles, and lying between 



oal details of the area. „ ] ,_..,_ ■? , 



23° 6' and 24° 29 , north latitude, and between 



72° 45' and 73° 39', east longitude. Physically it comprises the 



south-western prolongation of the ancient and much worn-down 



Aravalli hill-range, at a point where the latter is becoming 



obliterated by and merged into the low-level areas of Gujrat. 



It thus presents a diversified and picturesque country-side consisting 



of rocky hills, long sinuous hill ridges, and flat alluvial and sandy 



plains ; and it is well watered by the Sabarmati, Hathmati, Meshva, 



Majhani and Vatrak rivers. 



Previous to my visit this State had not been examined by the 



Geological Survev, with the exception of some 

 Previous Observe™. ^.^ ^ or ^ northem boimdary> 



touched by Mr. C. A. Hacket (late of the Geological Survey of 

 India) during his survey of Udaipur State about the year 1889, 

 and a similar but more limited band to the south near Ahmednagar 

 visited by Sub-Assistant Kishen Singh whilst surveying various 

 tracts in Bombay. The mapping by Hacket extended to sheet 

 144 of the Bombay Survey (121 of the Central India and Rajputana 

 Survey) as far as latitude 24°. This was coloured by him as his 

 " Aravalli System " in the plains, and as " Delhi Quartzite " in 

 the higher hill areas. Kishen Singh's work near Ahmednagar and 



