File:The Quarterly journal of the Geological Society of London (12684339895).jpg

1852.. STRICKLAND — UPPER LUDLOW ROCK AT HAGLEY PARK. 385
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a mile and a half further to the S.E., we come to the elevated region
of Woolhope, the axis of which runs for more than ten miles still in
a S.E. direction. It appears, therefore, that the ejection of the trap-
dyke at Bartestree, together with this protrusion of Silurian rocks at
Hagley Park, occur exactly on the axial line of the great eleyation of
Woolhope.
But though this coincidence of position deserves notice, yet the
forces which have caused these minor protru-
sions have in fact acted nearly at right angles
to the direction indicated. The Woolhope
region, though possessing an axis from N.W.
to S.E., is essentially an area, and not a line,
of elevation. Its pressures have been distri-
buted, not in two opposite directions from an
axis, but in every direction from a centre. In
conformity with this view we find that in its
north-western portion it is cut through by the
" great Mordiford fault," running N.E. by E.
(or nearly at right angles to the major axis),
and causing the strata about Dormington and
Stoke Edith to assume the same strike. Be-
yond the Woolhope area we find the valley of
the River Frome, the Bartestree Dyke, and
the protruded Silurian mass of Shucknall Hill
assuming almost exactly the same east-north-
easterly direction. And in the small dome-
like protrusion of Hagley Park, which lies
parallel to Bartestree Dyke, and precisely in
the axis of Shucknall Hill, we find a further
proof of the same movement.
It appears probable, then, that the pressure
caused by the elevation of the central dome
of the Woolhope area, acting in every direc-
tion, has on the north-west side caused great
undulations in the Silurian and Devonian strata
which lie beyond the region of actual elevation.
In two instances, that of Shucknall Hill and
of Hagley Park, the denudation of the Old
Red Sandstone has exposed to view the sub-
jacent Silurian rocks on the summits of these
undulations. Great shattering and disloca-
tion would of course accompany these move-
ments, and in the Bartestree Dyke it is inter-
esting to find one of the great crevices thus
formed, and filled with eruptive matter derived
from the Plutonic region where all these great
movements originated.
The accompanying section will serve to show
the relations in which the Hagley protrusion
stands to the Bartestree dyke and the Wool-