File:The Quarterly journal of the Geological Society of London (12684265173).jpg

114
PROCEEDINGS OF THE GEOLOGICAL SOCIETY. .Jan, 21,
Ridgway Range.
\
Sect. 17.
Fault.
The annexed diagram, fig. 7, will give the general bearing of the
N. and S. line of sections 14, 15, 16, and 17, and also their relation to
sections, on the S. side of the valley, before detailed.
In this section I have inserted the
Hastings sand .d) hypothetically. I
found on the north of the Purbeck
sections, and between the Purbeck
and the Chalk, a slight depression
of the surface, watered by a streamlet
and boggy. It seems, therefore, very
probable, looking at the stratigraphi-
cal details of the locality, that there
has been a severance of the Purbeck
and the overlying formation, giving
rise to this flow of water ; and the
3 boggy state of the ground would also
mark an argillaceous deposit, which
is the character of that portion of the
Hastings sand above the Purbeck, in
the same relative position one mile
further east at Ridgway.
18. (E. of last section) Purheck:
dip to N. by E. at 6°, and so in the
next field as far as it could be made
out.
19. (E. of old Ridgway road) Pur-
heck : dip to W.N.W. at 5°.
20. Purbeck : dip to N.N.W.
2 1 . Portland : dip to N. by E. at
15° to 20°.
22. Purheck : dip to N. by E. at
30°.
23. Purbeck : dip 55°.
^2
I*
Sect. 13.
Upway Valley.
Upway Church.
■^
sect. 3.

• Observations on the sections of the
  

Range N. of the Valley.
10 to 12. Show the west part of
i the valley to possess great regularity
1 of dip (to the N.).
g 14 to 16. Lead in this case to the
2 inference of the subsidence of the
e strata at Upway, resulting from a
local fracture of the Purbeck on its
general upheavement.
19. Shows to the observer of this large quarry a dip towards the
old Ridgway road, — a dip which here coincides in a great degree
with the natural dip of the country.
21 and 23. Show an alteration in the direction of the dip with an
inclination increasing to the E., and reaching its maximum at sec-