2 



HAYDEN : GEOLOGY OF NORTHERN AFGHANISTAN. 



The conditions under which my tour was made were peculiarly 

 unfavourable to systematic scientific work, and the prevailing ignorance 

 of the geological conditions of Afghanistan must be my excuse for pub- 

 lishing the following notes based on hasty and disconnected observa- 

 tions. The area traversed lies to the north and west of Kabul, and 

 includes the districts of Ghorband, Bamian, Saighan, and Kahmard, 

 The route followed lay from Kabul, via Koh-i-Daman to Ghorband, 

 thence across the Shibar pass and Kotal-i-Kashka to Bamian, through 

 Saighan and Kahmard, to the Kotal-i-Saozak (Sabz kotal). On either 

 side of this line, my reconnaissances extended as far as Barfak on the 

 east, and Khargin dara 1 (Western Saighan) on the west. The return 

 journev was made along the same route, except that, instead of return- 

 ing via Ghorband, I marched in from Bamian via Kalu, Gardan Diwal 

 on the Helmand, the valley of the Kabul river, and Arghandi. 



Throughout this area, the strike of the rocks is in the main S.W.- 

 N.E., and the dip northerly ; consequently, from Kabul outwards one 

 crosses an ascending series oE which the oldest member is found in the 

 Paghman range and in the hills around Kabul. The beds are almost 

 always greatly disturbed, and their relations often complicated by in- 

 trusive igneous rocks, both basic and acid. The prevailing tectonic 

 element is the reversed fold, the crest of which, as in the Himalaya, 

 leans over to the south ; the trend of the folds is, in the eastern parts 

 of the area, N.E.-S.W., gradually bending round to E.-W. in Bamian, 

 Western Saighan and Kahmard. 



The orographic features are largely influenced by the tectonic, and 

 the trend of the ranges and valleys corresponds closely with that of the 

 folds. This is particularly well-marked to the north of the Hindu 

 Kush, where such valleys as Saighan and Kahmard run for many miles 

 each parallel to a single fold. These valleys now appear to lie in syn- 

 clinal troughs, but their positions were no doubt originally determined 



1 Kotal — pass ; dara = valley or ravine. I have in most cases employed the 

 terms dara and kotal instead of their English equivalents, as they are usually 

 essential parts of the place names. 



