86 
HAYDEN : GEOLOGY OF SPITI. 
Giumal sandstone. 
Cretaceous. 
At Giumal, Kibber and Chikkim the Spiti shales are overlain, with 
interstratification, by hard, yellow and brown 
sandstones and quartzites, which constitute Sto- 
liczka's " Giumal sandstone," which was referred by him to the upper 
jurassic. Fossils are (airly common in the lower beds, many bivalves 
—usually, however, badly preserved — occurring near Giumal and 
Chikkim, while casts of Stepkanoceras and Perisphinctes were found 
near Kibber and Chikkim. These sandstones are undoubtedly of cre- 
taceous age. 
The highest member of the stratigraphical series of Spiti consists 
Chikkim limestone ^ °^ S""^)^ '^^ whitish limestone, about lOO 
and Chikkim shales, fget thick, overlain by soft, grey, calcareous 
shales. These beds form a synclinal on the summit of Chikkim 
"station," behind the village of the same name, and are found also 
in the upper reaches of the Lingti river, above Lilang. Fossils are 
very rare and appear to be confined to the limestone, which has 
yielded one belemnite, fragments of Rudistes and Foraminifera, in- 
cluding the genera Cristellaria, Dentalina and Haplophragmiuni. 
With the exception of the belemnite, all these fossils were found also 
by Stoliczka, who therefore referred the limestone to the cretaceous 
system. The overlying shales are greatly folded and their thickness 
cannot be determined, but it appears to be about 150 feet: in spite 
of careful search, no trace of fossils has been found in them. 
The first systematic account of the mesozoic rocks of Spiti was 
Stoliczka's nomen- g>ven by Stoliczka, who subdivided the whole 
group into the following series : — 
clature. 
Chikkim shales 
Chikkim limestone 
Giumal sandstone , 
Spiti shales . 
Tagling (upper) . 
Tagling (lower) . 
Para limestone 
Lilang limestone . 
I Cretaceous. 
I Jurassic. 
I Lias. 
Rhatic, 
Trias. 
