[part I. 



Chapter VII. — Sub-nummulitiCj tertiary^ and alluvium. 

 Immediately overlying the stratified traps, and resting usually upon 

 a crystalline concretionary amj^gdaloidal flow having often an iiTegular 

 surface, and weathering of a greenish rusty color, a singularly mixed and 

 varied band of rocks is found. 



It occurs as a narrow belt all round the upper portion of the traps 

 to the west, but has been seldom met with at their 



Position. ^ . 1 A • 



eastern termination about Buddresir and Anjar, 



being there perhaps concealed by an unconformable group forming the 



upper member of the tertiary system. Near this it re-appears, continuing 



to the neighbourhood of Buchao ; and it is also found entirely beyond 



the limits of the trap area in the Wagir tract, and on the south and 



south-eastern sides of the larger islands in the Kunn. 



It consists of soft variegated pseudo-brecciated or concretionary 



unctuous aluminous rocks of pale purple colors 

 The rocks. _ _ _ • 



mottled with white. Pure white varieties also 



occur, which soil the fingers, and sometimes contain disseminated grains 

 of white quartz ; and associated with these are strong red and mottled 

 laterites in places veined with haematite, in others containing agates. 

 Coarse sandstones largely composed of semi-transparent quartz grains 

 occur irregularly with purple or brown bands of silicious and ferruginous 

 rock resembling quartzite ; and the group also contains red or brown 

 gypseous and dark aluminous or white sandy shales fuU of leaf impres- 

 sions small resinous lumps, and carbonaceous layers ; some of the dark 

 beds being so bituminous as to burn readily at a candle j while from 

 others alum is manufactured at Mhurr. The whole group forms a series 

 beautifully varied both in texture and colour ; white or red, delicate 

 lavender, strong purple, and warm orange, tints prevailing. 

 ( 66 ) 



