6 PASCOE: GEOLOGICAL NOTES ON MESOPOTAMIA. 



right bank. A sigmoidal curve at Ain Dibs further relieves the 

 monotony. 



There is not a single tree in the area or within sight of it, and that 

 portion immediately east of Fathah is particularly barren of grass ; 

 towards Ain Nukhailah grass is more plentiful and water less scarce 

 though slightly brackish. The Jabal Makhul also supports more 

 vegetation. Small brown partridges like the Punjab sisi are plenti- 

 ful, especially, in the Makhul, and a few of a larger kind, similar 

 to the Indian chikhor, are to be found on the higher slopes ; these 

 and their usual companion, the fox, are the only forms of animal 

 life to claim attention. 



Exposures are excellent. The ground is much dissected by 

 streams and walking wearisome but not difficult owing to the soft- 

 ness of the strata. The ctopographical maps available were very 

 sketchy and at times ina curate, especially in their contours, but 

 they serve to show in a general way the structure of the area. The 

 geological boundaries, it is hoped, are as accurate as the maps 

 permit. The Alluvium is troublesome in concealing the Tertiaries 

 and has been omitted where possible ; to put in the true alluvial 

 boundary would necessitate a separate map. In the upper of the 

 two Tertiary series, the red clays and sandstones have been 

 separated from the sandstones and conglomerates ; these two divisions 

 therefore represent the Lower and Upper stages of that series, 

 which I have called the Kurd series. 



Rocks. 



The rocks comprise a central core of gypsiferous beds belonging 

 to the Fars, flanked on each side by the Kurd series consisting of 

 red clays and sandstones passing up into sandstones and con- 

 glomerates. The Mesopotamian Alluvium conceals much of the 

 latter series, but scarcely any of the Fars. Recent gravel is com- 

 mon, and an older conglomerate, probably of Pleistocene age, occurs 

 in small patches at considerable' heights near the river. 



Fars series. — The predominant constituent of the Fars beds 

 consists of white opaque gypsum, sometimes homogeneous and of 

 a high state o r purity, reaching thicknesses of 40 — 50 feet, at other 

 times stratified with numerous thin lamellae of c'ay. This deposit 

 is characterised by many underground caverns leached out by per- 

 colating water and sometimes several yards deep, which produce the 

 hollow sound ^o noticeable whe i walking on these beds. It 



