99 



Section II. — The Runn-Islajjd Range from Putchum to Chorar. 



The Putehum islandj out in the centre of the Runn, is traversed by 

 The Putchum Kala ^^° somewhat east and westerly chains of hills. Of 

 ^"""S^^- these that to the north called the Kala Doongur 



(Black hill) has the most lofty elevation found in Kntch, the summit of 

 Putchum Peer rising directly from the Runn to a height of 1,437 feet,* 

 by aneroid measurement. Like other portions of this chain, the north side 

 of the hills presents a steep scarp exposing contorted beds, which become 

 steady at the top and thence slope at low angles to the southward^ with 



Northern base of Put- 



long hanging levels. The contorted state of the 

 " """ '^^^' beds, at the north foot of the hills and numerous 



fissures filled with trap, render this part of the section obscure. The beds 

 here are about the lowest exposed in the Jurassic rocks of Kutch, and are 

 found to consist of fine white and light coloured silicious sandstone 

 with some calcareous bands and sandy slightly ferruginous purple beds; 

 pale flaggy sandstones also occur, and some peculiar yellowish rubbly 

 bands full of Nerinea, &c. There are also red and rusty shaly beds with 

 ripple marks, eonglomeritic, and thin shelly bands throughout ; but the 

 predominant varieties are white or light coloured sandstones often flaggy. 

 These are all of them more or less fossiliferous, the principal forms being 

 oysters, Coriula, turbinate Gastropoda ; and in Kooaree Beyt, among 

 beds ranging from soft raggy sandstone to hard sandy limestone with low 

 curving southerly and westerly dips, many highly fossiliferous layers 

 contain Cidaris spines, Trigonia, Natica and Nerinea. Intruded among 

 these lower beds are several doleritic dykes, one of red lava and a con- 

 siderable mass of black coarsely crystalline augitic trap with closer 

 grained olive veins, near Koorun-wand, which is highly magnetic, 



* Equal to a depressiou of 1'6 inches. 



