Prof. J. W. Gregory—Geology of Central Spitsbergen. 295 
Note on the Sequence across Central Spitsbergen from 
Advent Bay to Agardhs Bay. 
By J. W. Grecory, F.RS. 
HE collections described by Mr. Spath were made during 
Sir Martin Conway’s Expedition across Spitsbergen in 1896, and 
include also those then collected by Professor Garwood and presented 
by him to the British Museum of Natural History. 
The Mesozoic fossils were mainly obtained between Ice Fjord and 
Agardhs Bay, and especially along the Sassendal where the Triassic 
beds are well developed. The general relations are clearly shown in 
the northern side of that valley; the block at the western end is 
composed of Carboniferous rocks, which dip gently eastward and 
disappear under the black shales and flags of the Trias. 
Our route lay along the southern side of the Sassendal, where 
at the western end, ‘between Waterfall Camp and the shore of 
Ice Fjord, a conspicuous platform of Carboniferous rocks projects 
from the base of the escarpment. The Carboniferous rocks are 
represented by Productus Limestone in the two cliffs along the shore ; 
and further west, near Waterfall Camp, by cherts and coral lime- 
stone. 
The Carboniferous beds are covered by the Trias with a slight 
unconformity between them ; this was recognized by direct measure- 
ment at the angle between Sassendal and Fulmar Valley, where the 
Carboniferous beds dip 4° to south-south-west, and the Trias 2° to 
south-east. The general Triassic sequence is well exposed along the 
escarpment on the southern side of the valley, as in Sticky Keep to 
the west, and in the Trident to the east of the valley leading up to 
Brent Pass. The general succession in descending order may be 
summarized as follows :— 
Approximate 
thickness in 
Section I. feet. 
G. Plateau Flags: yellowish, unfossiliferous shaly flags : oe OO 
F. Upper Nodule bed. 
E. Oozy Mound beds: thin dark grey to black shales with 
phosphatic nodules. Fossils in three seams. 
(3) Upper seam—Belemnites. 400 
(2) Middle seam—Daonella, etc. 
(1) Lower seam—Nos. 31-5. 
These shales pass down to .shaly flags with the ribbed 
Pseudomonotis. } 
D. Escarpment Shales. 
(4) A 3in. Limestone. | 
(3) Thin paper shales with many Ammonites, reptilian 200 
bones, etc. 
(2) Middle Nodule bed. 
(1) Earthy Limestone. 
C.2. Black Shales and yellow flags; with fish, mollusca, etc., and 
many Posidonomya: (Professor Garwood found a reptile 600 
rib in the Trident) 
Lowest Nodule bed. 
Unfossiliferous black shales: few exposures. 500 
Carboniferous Limestone. 
Poe 
