26o VKEDENBURG: SKETCH OF BALOCHISTAN DESERT. 



The very distinct instance of a thrust-plane just mentioned will 

 help to understand a very curious feature which 



Saindak K6h. _ , , . . . . . . , , 



I have omitted to mention so far ; this is the 

 Saindak Koh, a mountain that rises to the east of Saindak spring. 

 The lower portion of the hill consists of the tertiary rocks that were 

 mentioned as forming a syncline ; owing to this structure the strata 

 (mostly shales) of the Saindak Koh belong to the highest eocene 

 horizon since they lie in the axis of the syncline over beds whose 

 fossils present affinities with the Nari fauna. The tertiary shales 

 are capped by a great mass of volcanic agglomerates and tuffs 

 similar to those that underlie the nummulitic strata. The junction 

 of this cap of agglomerates and of the tertiary shales is very sharply 

 defined and abrupt; it is not parallel with the planes of stratification 

 of the shales which are very greatly crushed at the junction. These 

 agglomerates are so similar to those normally underlying the tertiary 

 sediments that they must be regarded in all probability as the same 

 rock, and, considering the very distinct evidence of a thrust-plane in 

 the section above described, the same explanation must be resorted 

 to in order to account for their abnormal situation in the present 

 case. (See Fig. 15.) 



Here again we find as in so many other instances narrow dykes 

 of basalt. They run uninterrupted across the great thrust-plane, 

 indicating that they are much later in date than the earth-move- 

 ments which gave the rocks their present structure and situation. 



There are also veins of carbonate and sulphate of lime which 

 become metalliferous when they enter the abnormally situated 

 agglomerate. The ores which they contain are galena together with 

 small quantities of azurite and malachite. These minerals occur 

 very scantily although the lead is occasionally extracted. 



This locality is further interesting as the one where the highest 



Khirthar rocks at horizon was reC ognised amongst the marine 



Saindak. tertiary. Strata of Khirthar age were met 



with at Tafui (page 47), but in the present case the series appears to 



ascend up to the base of the Nari or uppermost eocene. 



( 82 ) 



