stripes
Occurrence number:
162-00-014
Country:
Tajikistan
Location:
Longitude: 74.92, Latitude: 37.8
Carbonatite:
No
This northern group of pipes is related to a regional fault that separates geological zones of the central and southwestern Pamirs. The explosion pipes and plugs, with some dykes, which were discovered by Dmitriev (1976), form a 15 km long chain. The pipes are up to 100 m in diameter, are commonly multiple and contain tuffs and breccias as well as massive rocks. The 'Leucite pipe' illustrated in Fig. 103 has a border zone of porphyritic pyroxene-sanidine syenite and fergusite with the central part occupied by fergusite explosion tuffs and pseudoleucite phonolite.
Age:
K-Ar on K-feldspar gave 14 Ma.
References:
DMITRIEV, E.A. 1976. Cainozoic potassic alkaline rocks of East Pamir. Donish, Dushanbe. 170 pp.
Map:
Fig. 2_103. 'Leucite pipe' one of the group of Northern Pipes in the Pamirs (after Dmitriev, 1976, Fig. 5).
Location: