30 PASCOE: GEOLOGICAL NOTES ON MESOPOTAMIA. 



pitching towards Shura would, in the latter eventuality, be wortb 

 further investigation. The relationship of this and the Mishrak 

 fold to that of the Jabal Kibritiyah, some distance further west, 

 was not worked out ; the latter signifies " Sulphur range," so that 

 sulphur indications are evidently plentiful and oil seepages not 

 improbable, though none of the latter were reported to me. If 

 oil should be found in the Mishrak fold, the country from the river 

 to the Jabal Kibritiyah and in and around the latter, and also 

 the hills north of the Wadi-al-Adba, ought to be topographically sur- 

 veyed on a 4 ins. to 1 mile scale, so that the geological, structure 

 may be worked out in detail, and the capabilities of some of the 

 minor puckers and rolls estimated from an oil-winning point of 

 view. 



Sulphur. 

 The sulphur in the Tigris branch is described in Report No. 7. 



Road-metal. 



I was frequently asked by Sappers and Pioneers advice as to 

 road-metal. As stated in a former report, the coarser varieties 

 of the gravel of siliceous pebbles which so frequently borders the 

 river, would furnish an excellent road-metal, provided it is broken 

 into angular fragments. But since the difficulty regarding roads, 

 between Sharqat and Mosul for instance and in many other places, is 

 not so much to prevent wear and tear of the surface, but to prevent 

 portions of the road subsiding or shifting bodily, I think broken 

 angular fragments of limestone, which may be locally more plentiful 

 than the gravel and is certainly more easily broken up, would do 

 equally well. So long as the road is properly ditched and drained, 

 limestone " metal " would probably serve the purpose as well as 

 the harder chert and sandstone of the gravel pebbles. An experi- 

 mental section of road made of limestone mixed with a little gypsum 

 would be interesting. I have seen uncrushed gravel pebbles being, 

 used on the roads; this produces a very transient sort of structure 

 and seems scarcely worth the trouble of putting down. 



12th January, 1919. 



